                 FOR PUBLICATION
 UNITED STATES COURT OF APPEALS
      FOR THE NINTH CIRCUIT

UNITED STATES OF AMERICA,             
                Plaintiff-Appellee,         No. 07-30219
               v.                            D.C. No.
RICHARD ORLAND DAVIS,                     CR-04-30061-ALA
             Defendant-Appellant.
                                      

UNITED STATES OF AMERICA,             
                Plaintiff-Appellee,        No. 07-30220
               v.                           D.C. No.
                                           CR-04-30061-
CYNTHIA JEAN DAVIS,                           02-AA
             Defendant-Appellant.
                                      

UNITED STATES OF AMERICA,                 No. 07-30226
                Plaintiff-Appellee,
               v.                           D.C. No.
                                          CR-04-30061-AA
JEFFREY ALLEN DAVIS,
                                             OPINION
             Defendant-Appellant.
                                      
       Appeal from the United States District Court
                for the District of Oregon
         Ann L. Aiken, District Judge, Presiding

                  Argued and Submitted
              May 5, 2008—Portland, Oregon

                    Filed June 30, 2008
                           7753
7754                 UNITED STATES v. DAVIS
       Before: Richard C. Tallman, Richard R. Clifton, and
                N. Randy Smith, Circuit Judges.

                 Opinion by Judge N.R. Smith
                       UNITED STATES v. DAVIS                       7757


                             COUNSEL

Steven Jacobsen, Assistant Federal Public Defender, Portland,
Oregon, for defendant-appellant Jeffrey Allen Davis.

Marc Friedman, Eugene, Oregon, for defendant-appellant
Cynthia Jean Davis.

Robert M. Stone, Medford, Oregon, for defendant-appellant
Richard Orland Davis.

Karin J. Immergut, United States Attorney, District of Ore-
gon; Douglas W. Fong, Assistant United States Attorney,
Medford, Oregon, for the plaintiff-appellee.


                              OPINION

N.R. SMITH, Circuit Judge:

   On October 22, 2004, law enforcement agents executed a
search warrant and raided a large marijuana growing opera-
tion on private property in rural Oregon belonging to Jeffrey
and Cynthia Davis. While officers were executing the search
warrant on the Davis’s property,1 Jeffrey Davis’s brother,
Richard Davis, drove onto the property through a locked gate




  1
    To avoid confusion because the three appellants share the last name
Davis, we generally refer to Jeffrey and Cynthia Davis by their respective
full names. Any possessive use of “the Davis’s” refers to Jeffrey and Cyn-
thia Davis collectively. We refer to Richard Davis by his full name
throughout.
7758                UNITED STATES v. DAVIS
and, when asked, told officers in a moment of omniscient
honesty that he knew “everything” about the marijuana grow-
ing operation.

   We hold that the observations, upon which law enforce-
ment officers relied to obtain the warrant to search the Davis’s
property, were not made within the curtilage of the Davis’s
home. As a result, the warrant did not violate the Davis’s
Fourth Amendment rights. We must also determine whether
the law enforcement officers violated Richard Davis’s consti-
tutional rights by questioning him, searching his person,
searching his vehicle, and subsequently searching his prop-
erty. With the exception of the search of a tin container found
on Richard Davis’s person, our answer is no. But because any
error arising from its discovery was harmless, the motions to
suppress all evidence seized were properly denied.

   We have jurisdiction pursuant to 28 U.S.C. § 1291. We
affirm.

                               I.

                              A.

   In the fall of 2004, Pete Jenista, a narcotics detective in
Josephine County, Oregon received a tip from a confidential
informant about a marijuana growing operation at 2010 Stew-
art Road in Grants Pass, Oregon. Detective Jenista determined
that the eighty-acre parcel of land at that address was owned
by Jeffrey and Cynthia Davis and that they lived on the prop-
erty with their daughter, Heather. The property is bordered by
land owned by the Bureau of Land Management to the east
and west. Cynthia Davis (herself) owned the property directly
adjoining 2010 Stewart Road to the south. Richard Davis
owned a forty-acre parcel of land approximately a half-mile
away which was only accessible using the same road that
accesses the 2010 Stewart Road property.
                     UNITED STATES v. DAVIS                  7759
   At the time Jeffrey and Cynthia Davis purchased the prop-
erty at 2010 Stewart Road in the mid-1990s, it did not contain
a homesite. The property is extremely rural, heavily wooded,
and hilly. The closest home is almost a half-mile away. Jef-
frey and Cynthia Davis developed the property, building a
home and a large workshop. The workshop was set well apart
from the house and partially surrounded by a chain-link fence.
Inside the workshop, in addition to the marijuana growing
operation, there was a freezer and refrigerator-freezer, a walk-
in 700 bottle wine cellar, a shower, toilet, and a urinal. Jeffrey
and Cynthia Davis stored Christmas materials and tools in the
workshop and used a barbeque pit under the workshop’s
awning for barbeques.

   At approximately 9:30 p.m. on October 12, 2004, Detective
Jenista met two other detectives and drove to the area where
Stewart Road turns from pavement to gravel. The detectives
continued up the gravel road on foot approximately 300 feet,
where they proceeded past an electric gate. The gate, which
was donated by Jeffrey and Richard Davis, sits on property
belonging to a nearby Girl Scouts camp. It is used to access
the Davis’s property, the Girl Scouts camp, and the BLM
property. Multiple parties have access codes to the gate.
When the detectives proceeded past the gate, they did not see
two no trespassing signs, which were laying on the ground
near the gate. Additionally, there was a posted sign near the
gate which read:

    Winema Girl Scout Council
    This road is for access to private property and Camp
    Ruth Hyde only!
    No hunting or motorcycling!
    It is closed to all others!

The detectives also passed a similar Girl Scouts’ sign posted
a short distance beyond the gate.

   When the detectives got within approximately 500 feet of
the Davis’s residence, numerous outdoor lights illuminated
7760                UNITED STATES v. DAVIS
the residence and the area in and around the large workshop.
Detective Jenista heard the sound of a generator running from
the direction of the large shop. He also smelled an odor,
which he identified from experience as the odor of green-
growing marijuana. Another detective also smelled the mari-
juana odor.

   The detectives then left the road and walked through the
woods along an old unused skid road toward the Davis’s
workshop. A dirt barrier had been erected to prevent vehicles
from driving on the skid road. The detectives followed the
skid road to the southernmost portion of a pond on the
Davis’s property near the workshop. To reach the workshop
without being seen, the detectives circled the pond to the
south and east, walking through a very heavily wooded gully.
When they came out of the gully, the detectives were at the
bottom of a short, steep embankment below the workshop. At
that location, the detectives were able to observe the chain-
link fence around the workshop. Both the workshop and the
area around the workshop were extremely well-lit, and the
detectives were able to observe commercial equipment inside
the workshop. They did not observe anything to indicate
domestic activity.

   The detectives next walked up the embankment to the edge
of the fence, where they observed steam coming off the top
of the building and heard the sound of the generator more
clearly. The detectives walked along the outside of the fence
to the northeast. As they approached the area adjacent to the
workshop itself, the brush and trees became extremely heavy,
and the embankment became very steep. Just inside the heavi-
est brush, the detectives saw a light-colored pipe sticking out
of the embankment, facing southeast, which was approxi-
mately a foot or more in diameter. The pipe protruded from
the steeply angled embankment, approximately five to six feet
outside of the chain-link fence. Detective Jenista placed his
hand in front of the pipe and felt warm, humid air being
pushed out. He also placed his head near the entrance of the
                    UNITED STATES v. DAVIS                7761
pipe, smelled the odor of green-growing marijuana, and heard
an exhaust fan somewhere down the length of the pipe. The
detectives then left the area near the workshop and returned
to the gravel roadway, again smelling marijuana at the same
location where it originally caught their attention.

   On October 21, 2004, the detectives obtained a search war-
rant based on Detective Jenista’s affidavit describing his
observations on the Davis’s property. On October 22, 2004,
twelve to fifteen officers and agents from various law
enforcement agencies executed the search warrant. The offi-
cers discovered approximately 3,200 green-growing mari-
juana plants, approximately 60 pounds of dry, processed
marijuana which had been prepared for sale, approximately
$50,000 in a safe, and over sixty firearms.

                              B.

   While officers were executing the search warrant, Richard
Davis drove onto the property. Richard Davis exited his vehi-
cle and asked two approaching deputies what was going on.
The deputies informed him that they were executing a search
warrant. Richard Davis asked more questions, but the deputies
informed him that he needed to speak to one of the detectives,
and that he needed to be read the search warrant. While Rich-
ard Davis waited to be read the search warrant, the deputies
continued conversing with him. Reserve Deputy Andrew
Aguinaga asked Richard Davis why he was there. He
responded that he was on the property to see his brother. Dep-
uty Aguinaga obtained Richard Davis’s name, date of birth,
and asked him “if he could grab his driver’s license, and while
he was near his vehicle if he could possibly move it out of the
way so that [the officers’] vehicles could enter the driveway.”
At some point during the encounter, Richard Davis asked if
he could leave. Deputy Aguinaga informed Richard Davis
that he could not, presumably because he had not yet been
read the warrant. After Richard Davis moved his vehicle and
retrieved his identification, Deputy Aguinaga gave Richard
7762               UNITED STATES v. DAVIS
Davis’s driver’s license to Agent Ronald Wright of the Drug
Enforcement Administration. Deputy Aguinaga’s entire con-
tact with Richard Davis lasted less than ten minutes.

   Meanwhile, another deputy summoned Sheriff’s Sergeant
Ken Selig to speak with Richard Davis. When he arrived to
the driveway area, Sergeant Selig, who supervised the Jose-
phine County Sheriff’s Office Interagency Narcotics unit,
read the search warrant to Richard Davis. Sergeant Selig then
observed while reserve deputies searched Richard Davis. The
deputies found hashish oil in a tin on Richard Davis’s person.
Sergeant Selig then introduced Richard Davis to Agent
Wright and departed. Sergeant Selig’s entire contact with
Richard Davis lasted approximately ten to fifteen minutes.

   While Richard Davis was still standing in the driveway,
Agent Wright asked him questions regarding his living situa-
tion. According to Richard Davis, the conversation was “casu-
al” and “low-key.” Richard Davis was not in handcuffs, and
Agent Wright did not tell him he was under arrest. Agent
Wright did not know whether Richard Davis had been
searched or frisked prior to his contact with him. Agent
Wright asked Richard Davis what he knew about “what was
going on in the large shop . . . where the marijuana grow was
located.” Richard Davis responded “everything.” Agent
Wright then asked a follow-up question about Richard
Davis’s role in the operation to which Richard Davis
responded that he “helped.” Agent Wright inquired how long
he had been involved, and Richard Davis then stated that he
thought he ought to talk to an attorney. At that point, Agent
Wright stopped the conversation. Either Sergeant Selig or one
of Selig’s deputies escorted Richard Davis to the main resi-
dence. At some point before he was escorted to the main resi-
dence, but after talking to Agent Wright, Richard Davis was
handcuffed. Agent Wright’s entire contact with Richard Davis
lasted five to ten minutes.

  After Richard Davis was escorted to the main residence,
Agent Wright searched Richard Davis’s vehicle. There,
                   UNITED STATES v. DAVIS                7763
Wright found handguns, thousands of dollars in cash, and a
pair of scissors with a residue stain. Officers used the evi-
dence found in Richard Davis’s vehicle, along with his state-
ments, to obtain a warrant to search his property on Lower
River Road, approximately a half-mile away from the Davis’s
property at 2010 Stewart Road. Officers found another 150
marijuana plants growing at the Lower River Road property.

                             C.

   On March 7, 2005, a superseding indictment was filed
charging Jeffrey Davis, Cynthia Davis, Richard Davis, and
Kyle Blondin (Jeffrey Davis’ daughter’s boyfriend) with: 1)
conspiracy to manufacture 1,000 or more marijuana plants in
violation of 21 U.S.C. § 841(a)(1), (b)(1)(A)(vii), and 21
U.S.C. § 846; and 2) manufacture of more than 1,000 mari-
juana plants in violation of 21 U.S.C. § 841(a)(1),
(b)(1)(A)(vii). The indictment further alleged that all defen-
dants were involved in manufacturing 3,000 or more mari-
juana plants.

   Jeffrey Davis was also charged with possession of an
unregistered destructive device, a “Street Sweeper” revolving
cylinder shotgun, in violation of 26 U.S.C. § 5861(d), and two
counts of possession of an unregistered machine gun in viola-
tion of 26 U.S.C. § 5861(d). Richard Davis was also charged
with one count of possession of an unregistered destructive
device for possessing the “Street Sweeper.”

   On October 31, 2005, Jeffrey Davis filed a motion to sup-
press all of the evidence and statements obtained as a result
of the search of the Davis property. Cynthia Davis and Rich-
ard Davis joined the motion. Jeffrey Davis argued that the
government relied upon observations made within the curti-
lage of the Davis home in order to obtain a search warrant and
that, without the challenged observations, probable cause for
the search warrant was lacking.
7764                UNITED STATES v. DAVIS
   On November 15, 2005, Richard Davis filed a separate
motion to suppress, which Jeffrey Davis joined. Richard
Davis argued that the warrant used to search the Davis resi-
dence was overly broad as it applied to him and his vehicle.
Richard Davis also argued that, because law enforcement offi-
cers never read him the Miranda warnings, his statements and
the fruit of those statements should be suppressed. See
Miranda v. Arizona, 384 U.S. 436, 444-45 (1966).

   On May 24, 2006, the district court denied Jeffrey Davis’s
motion to suppress. The district court concluded that: 1) in the
course of gathering information for the search warrant, the
detectives did not enter the curtilage of the Davis’s home; and
2) as a result, the search did not violate the Fourth Amend-
ment. The court noted that the government had argued that
Richard Davis possessed no reasonable expectation of privacy
in his brother’s house or shop and therefore could not contest
the validity of the search, but declined to reach the merits of
that argument.

   The district court also denied Richard Davis’s motion to
suppress. The court held that, because Richard Davis was not
“in custody” at the time that he was questioned, he was not
entitled to receive Miranda warnings. The district court also
held: 1) that the search warrant authorizing the search of all
vehicles visiting or frequenting the property was not facially
overbroad; and 2) that Richard Davis’s statements and the dis-
covery of hashish oil on his person independently gave rise to
probable cause to search his vehicle.

   On October 11, 2006, both Jeffrey Davis and Richard
Davis pled guilty to one count each of manufacture of mari-
juana, and one count each of possession of an unregistered
destructive device. On the same day, Cythnia Davis pled
guilty to conspiracy to manufacture marijuana. All three
entered conditional pleas, preserving their right to appeal the
denial of their motions to suppress. All three now separately
                     UNITED STATES v. DAVIS                  7765
appeal the district court’s denial of those motions. We consol-
idated their appeals.

                               II.

   We review de novo the denial of a motion to suppress,
while the underlying factual findings are reviewed for clear
error. United States v. Crawford, 372 F.3d 1048, 1053 (9th
Cir. 2004) (en banc). In so reviewing, we also review de
novo: 1) whether an area of land is protected under the Fourth
Amendment as the curtilage of a dwelling house, United
States v. Barajas-Avalos, 377 F.3d 1040, 1054 (9th Cir. 2004)
(citing United States v. Johnson, 256 F.3d 895, 909 n.1 (9th
Cir. 2001) (en banc)); 2) whether a suspect is “in custody” for
purposes of Miranda, United States v. Kim, 292 F.3d 969, 973
(9th Cir. 2002); 3) the district court’s reasonable suspicion
determinations, United States v. Arvizu, 534 U.S. 266, 275
(2002); and 4) the district court’s determination of probable
cause, United States v. Pinela-Hernandez, 262 F.3d 974, 977
(9th Cir. 2001).

                               III.

   Jeffrey, Cynthia, and Richard Davis all argue that the
detectives violated their Fourth Amendment rights by entering
the clearing around the Davis’s home, which contained the
main house, workshop, and pond. Specifically, all three argue
that this area constitutes the curtilage of the home and,
because the detectives entered without a warrant, none of their
observations can be considered in determining whether Detec-
tive Jenista’s affidavit set forth sufficient facts to justify the
issuance of a search warrant. Jeffrey, Cynthia, and Richard
Davis further argue that Detective Jenista’s affidavit does not
set forth sufficient facts to establish probable cause to search
the property at 2010 Stewart Road, if the observations of the
detectives during their alleged trespass onto the property are
excised from the affidavit.
7766                UNITED STATES v. DAVIS
   [1] “For the purposes of the Fourth Amendment, curtilage
. . . extends to a larger area the right to privacy a person
enjoys inside the home . . . .” United States v. Gorman, 104
F.3d 272, 274 (9th Cir. 1996) (citing Oliver v. United States,
466 U.S. 170, 178 (1984)). In United States v. Dunn, 480 U.S.
294, 301 (1987), the Supreme Court held that “curtilage ques-
tions should be resolved with particular reference to four fac-
tors,” including: (1) “the proximity of the area claimed to be
curtilage to the home,” (2) “whether the area is included
within an enclosure surrounding the home,” (3) “the nature of
the uses to which the area is put,” and (4) “the steps taken by
the resident to protect the area from observation by people
passing by.” These factors “are useful analytical tools only to
the degree that, in any given case, they bear upon the centrally
relevant consideration — whether the area in question is so
intimately tied to the home itself that it should be placed
under the home’s ‘umbrella’ of Fourth Amendment protec-
tion.” Id. We address each of the four Dunn factors in turn.

                              A.

   [2] There is not any “fixed distance at which curtilage
ends.” United States v. Depew, 8 F.3d 1424, 1427 (9th Cir.
1993), overruled on other grounds by Johnson, 256 F.3d at
911-14. In Dunn, the area near a barn from which officers
made observations was approximately 60 yards from the
house on the property. 480 U.S. at 302. The Court stated that
180 feet was a “substantial distance support[ing] no inference
that the barn should be treated as an adjunct of the house.” Id.
Like the barn in Dunn, the area near the Davis’s workshop
was located approximately 180 feet from the house. Addition-
ally, the exhaust pipe where Detective Jenista made the
majority of his incriminating observations was more than 200
feet from the Davis’s house. Thus, standing alone, the prox-
imity factor weighs against finding that the area outside of the
Davis’s workshop lay within the curtilage. The fact that the
Davis’s property was rural does not change our analysis. In
                    UNITED STATES v. DAVIS                  7767
Dunn, the defendant’s property was equally rural and more
than 100 acres larger than the Davis’s property. See id. at 297.

                               B.

   “ ‘[F]or most homes, the boundaries of the curtilage will be
clearly marked; and the conception defining the curtilage —
as the area around the home to which the activity of home life
extends — is a familiar one easily understood from our daily
experience.’ ” Id. at 302 (quoting Oliver, 466 U.S. at 182
n.12). Although not conclusive, “[f]encing configurations are
important factors in defining the curtilage.” Id. at 301 n.4.

   [3] Here, the Davis’s workshop was not within any enclo-
sure that also encompassed the house. In fact, the workshop
was set apart from the house and other areas of the Davis’s
property by a separate chain-link fence. Even if we accepted
that the workshop itself was part of the curtilage, all of Detec-
tive Jenista’s observations were made from the area outside
the fence. Further, the exhaust pipe, which offered the most
incriminating evidence, protruded from a steep embankment
outside the fence and was hidden in trees and heavy brush.
Accordingly, the area around the workshop and the area
where the exhaust pipe was located “stand[ ] out as a distinct
portion of [the Davis’s property], quite separate from the resi-
dence.” Id. at 302.

                               C.

   In Dunn, the Court analyzed the use of the barn at issue in
that case from the point of view of officers approaching the
area, and in light of its actual use. See id. at 302-03; see also
Johnson, 256 F.3d at 917 (Kozinski, J. concurring in part, dis-
senting in part) (noting that this Court has emphasized both
actual use and “what an observer standing outside the struc-
ture could have known”). When analyzing the nature of the
uses to which the area in question is put, the Supreme Court
has found it “especially significant that the law enforcement
7768                UNITED STATES v. DAVIS
officials possessed objective data indicating that the [area]
was not being used for intimate activities of the home.” Dunn,
480 U.S. at 302.

   Although there is some evidence that Jeffrey and Cynthia
Davis used the workshop to store bulk food, wine, and Christ-
mas decorations, the detectives smelled the marijuana while
standing in an area outside the workshop. Thus, we need not
decide whether the interior of the workshop fell within the
curtilage. See United States v. Van Damme, 48 F.3d 461, 465
(9th Cir. 1995) (holding that where officers smelled marijuana
from outside greenhouses, there was “[no] need to reach the
question of whether the interior of the greenhouses constituted
‘open fields’ ”).

   [4] From an objective standpoint, the detectives had
received a tip that there was a large marijuana growing opera-
tion on the property. From the area outside the workshop, the
detectives observed no sign of domestic activity. Instead, they
heard a generator running, observed extremely bright lights,
and smelled the odor of marijuana. All of these observations
were consistent with a marijuana growing operation, which is
not an “intimate activity of the home.” See id. at 464 (“The
cultivation of crops, such as marijuana, is one of those activi-
ties that occur in ‘open fields,’ not an intimate activity of the
home.” (citing Oliver, 466 U.S. at 179)). Finally, the exhaust
pipe protruding the embankment was hidden in a wooded
area, with no signs of domestication. Thus, the use of the area
in question also weighs against a finding that it was within the
curtilage of the Davis’s home.

                               D.

   The last Dunn factor requires us to consider the extent to
which Jeffrey and Cynthia Davis attempted “to protect [the
area alleged to be curtilage] from observation by those stand-
ing in the open fields.” 480 U.S. at 303. Jeffrey, Cynthia, and
Richard Davis all emphasize the fact that the property lay
                    UNITED STATES v. DAVIS                 7769
behind an electric gate and several no trespassing signs. The
remote location of the property, the electric gate, and the fact
that the house, workshop and pond were surrounded by heavy
woods all suggest that the Davis’s chose this property because
it was not easily viewed by passers-by. See Depew, 8 F.3d at
1428.

   However, our inquiry focuses on the extent to which Jef-
frey and Cynthia Davis attempted to protect the area around
the workshop and exhaust pipe from view, not the entire prop-
erty. See, e.g., United States v. Traynor, 990 F.2d 1153, 1158-
59 (9th Cir. 1993), overruled on other grounds by Johnson,
256 F.3d at 911-14. Near the workshop itself, there was a
chain-link fence which, by its nature, is not designed to pre-
vent observation. There was also a sign on the fence which
read, “This dog can make it to the fence in three seconds can
you?” However, “the presence of a ‘No Trespassing’ sign
does not itself create a legitimate expectation of privacy.” Id.
at 1159 (citing Oliver, 466 U.S. at 182). Nothing, other than
the property’s remote location and trees, prevented the detec-
tives from observing the area around the workshop or exhaust
pipe. Thus, at best, this factor is neutral.

   [5] Considered together, the Dunn factors weigh against a
finding that the area outside the fence around the workshop,
including the area where the exhaust pipe was located lay
within the curtilage of the Davis’s property. The detectives
first smelled the marijuana well before they neared the work-
shop. The workshop itself was set nearly 200 feet from the
house and set apart from the house by a fence. The detectives
observed no domestic activity from the area outside the work-
shop and apart from the natural topography of the property,
it was not shielded from view. Additionally, the exhaust pipe
extended beyond the fence protecting the workshop in a
wooded area where no domestic activity occurred.

   [6] We hold that neither the area around the workshop nor
the area where the exhaust pipe was located was an area “inti-
7770                   UNITED STATES v. DAVIS
mately tied to the home itself.” See Dunn, 480 U.S. at 301.
Accordingly, the detectives did not violate the Fourth Amend-
ment rights of Jeffrey, Cynthia, or Richard Davis and Detec-
tive Jenista’s observations established probable cause for the
search warrant of 2010 Stewart Road.2 Thus, the district court
correctly denied Jeffrey Davis’s motion to suppress.

                                  IV.

  We next turn to Richard Davis’s claims that law enforce-
ment officers violated his Fourth Amendment rights by: 1)
detaining him; 2) questioning him; 3) frisking him; 4) search-
ing his vehicle; and 5) searching his property at Lower River
Road.

                                   A.

   [7] Richard Davis first argues that the district court should
have suppressed both his statements and the officers’ subse-
quent searches of his vehicle and property because the depu-
ties initial detention of him when he drove onto his brother’s
property violated his Fourth Amendment right to be secure
against an unreasonable seizure of his person. The traditional
rule is that “an official seizure of [a] person must be sup-
ported by probable cause, even if no formal arrest is made.”
Michigan v. Summers, 452 U.S. 692, 696 (1981) (citing
Dunaway v. New York, 442 U.S. 200 (1979)). However, some
seizures which would fall under this general rule “constitute
such limited intrusions on the personal security of those
detained and are justified by such substantial law enforcement
interests that they may be made on less than probable cause,
so long as police have an articulable basis for suspecting
criminal activity.” Id. at 699; see, e.g., Terry v. Ohio, 392
U.S. 1, 21-22 (1968). A seizure effected by law enforcement
while executing a valid search warrant falls within this limited
  2
  Like the district court, we need not reach the issue of whether Richard
Davis had a reasonable expectation of privacy in the Davis’s workshop.
                    UNITED STATES v. DAVIS                  7771
exception. “[F]or Fourth Amendment purposes . . . a warrant
to search for contraband founded on probable cause implicitly
carries with it the limited authority to detain the occupants of
the premises while a proper search is conducted.” Summers,
452 U.S. at 705 (footnote omitted). “An officer’s authority to
detain incident to a search is categorical; it does not depend
on the ‘quantum of proof justifying detention or the extent of
the intrusion to be imposed by the seizure.’ ” Muehler v.
Mena, 544 U.S. 93, 98 (2005) (quoting Summers, 452 U.S. at
705 n.19).

   [8] We have rejected attempts to distinguish Summers
based on the facts that a detainee has no ownership interest in
the property being searched or that the detainee was not at the
premises when detained. See United States v. Taylor, 716
F.2d 701, 707 (9th Cir. 1983) (“The Court clearly framed
Summers in terms of ‘occupants,’ not owners, and explicitly
found no constitutional significance in the fact that some of
the ‘occupants’ were seized on the sidewalk as they were
leaving the house.”). The Sixth Circuit has addressed a factual
scenario like that presented here and reasoned that the deten-
tion of a non-resident was permissible based upon both officer
safety and the legitimate interest in preventing flight in the
event incriminating evidence was found. See United States v.
Bohannon, 225 F.3d 615, 617 (6th Cir. 2000) (concluding that
even though the person detained was not inside the residence,
and had pulled up in a car as the officers were concluding
their search, “[t]he policy justifications of Summers . . . espe-
cially to protect officers’ safety, are applicable”). We agree.

   [9] Although Richard Davis was not present at his brother’s
property when the officers began executing the constitution-
ally valid search warrant, he arrived in the midst of the search.
At the time Richard Davis arrived at the property, the officers
knew that: 1) the property contained a large marijuana grow-
ing operation; and 2) in order to reach the property during the
search, Richard Davis had passed through an electric gate
which was closed, and to which only a limited number of par-
7772                UNITED STATES v. DAVIS
ties had the code. Therefore, the police “could reasonably
infer” that he was involved in criminal activity. See Bohan-
non, 225 F.3d at 617. Given the circumstances of his arrival
at the scene of the execution of the search warrant, Richard
Davis’s detention was justified both by the need for both offi-
cers’ safety and “the legitimate law enforcement interest in
preventing flight in the event that incriminating evidence is
found” and did not violate his Fourth Amendment rights. See
Summers, 452 U.S. at 702. Thus, the district court did not err
by concluding that the officers’ actions were “reasonable and
necessary procedures to secure the premises during the
search.”

                              B.

   Richard Davis also contends that: 1) he was in custody for
Miranda purposes at the time Agent Wright questioned him;
and 2) because he was not given Miranda warnings, the dis-
trict court should have suppressed both his statements to
Agent Wright and the subsequent fruit of those statements.
“[W]hether an individual detained during the execution of a
search warrant has been unreasonably seized for Fourth
Amendment purposes and whether that individual is ‘in cus-
tody’ for Miranda purposes are two different issues.” United
States v. Kim, 292 F.3d at 976. Where an individual has been
detained incident to a search warrant, and officers’ question-
ing stays within the bounds of questioning permitted during
a Terry stop, Miranda rights are not required. See id. (citing
Berkemer v. McCarthy, 468 U.S. 420, 439-40 (1984)). If,
however, the individual is asked questions going “beyond a
brief Terry-type inquiry,” the individual is entitled to Miranda
warnings. Id.

   Because we hold that Richard Davis was detained incident
to the execution of a search warrant, we must determine
whether the officers’ questioning of him stayed within the
bounds of those permitted during a Terry stop. During a Terry
stop, officers “may ask the detainee a moderate number of
                    UNITED STATES v. DAVIS                  7773
questions to determine his identity and to try to obtain infor-
mation confirming or dispelling the officer’s suspicions.”
Berkemer, 468 U.S. at 439.

   During Richard Davis’s initial encounter with the deputies,
he was very briefly questioned about who he was and why he
was on the property. Richard Davis was next questioned by
Agent Wright. In his conversation with Agent Wright (which
Richard Davis described as “casual” and “low-key”), Agent
Wright asked Richard Davis about his living situation and
what he knew about “what was going on in the large shop . . .
where the marijuana grow was located.” After Richard Davis
responded, “everything,” Agent Wright asked a follow-up
question about Richard Davis’s role in the operation. Agent
Wright then asked another follow-up question about how long
Richard Davis had been involved in the operation.

   [10] None of these questions went beyond those that would
normally be permissible during a Terry stop. The total number
of questions asked of Richard Davis by law enforcement offi-
cers was minimal. The deputies’ initial questions were
directed at determining Richard Davis’s identity and reason
for being on the property. The four or so questions asked by
Agent Wright were all aimed at obtaining information to con-
firm or dispel Agent Wright’s suspicion that Richard Davis
might be part of the marijuana growing operation given that
he was related to the property owners and arrived at the prop-
erty via a locked, electric gate. Accordingly, law enforcement
officers were not required to advise Richard Davis of his
Miranda rights. See Kim, 292 F.3d at 976.

                               C.

   Richard Davis next argues that the evidence found as a
result of the search of his person must be suppressed because
the frisk violated his Fourth Amendment rights. Generally, if
an officer has a reasonable articulable suspicion that a person
“pose[s] a threat to his safety or the safety of others, he [can]
7774                UNITED STATES v. DAVIS
detain him to conduct an investigatory, ‘pat down’ frisk, con-
sistent with the Fourth Amendment’s prohibition against
‘unreasonable searches and seizures.’ ” United States v.
Terry-Crespo, 356 F.3d 1170, 1173 (9th Cir. 2004) (quoting
United States v. Sokolow, 490 U.S. 1, 7 (1989)). “The ‘narrow
scope’ of the Terry exception does not permit a frisk for
weapons on less than reasonable belief or suspicion directed
at the person to be frisked, even though that person happens
to be on premises where an authorized narcotics search is tak-
ing place.” Ybarra v. Illinois, 444 U.S. 85, 94 (1979).

   Thus, the officers’ frisk of Richard Davis violated the
Fourth Amendment unless they had a reasonable belief or sus-
picion that he could be armed or posed a threat to their safety.
There is no testimony in the record that the officers observed
any suspicious bulges, that Richard Davis’ demeanor aroused
the officer’s concern, or that he acted in a threatening manner.
See United States v. Flatter, 456 F.3d 1154, 1157-58 (9th Cir.
2006) (noting factors supporting reasonable belief that an
individual would be armed, and concluding that none of the
factors was present). However, at the time they frisked Rich-
ard Davis, the officers knew that: 1) the property contained a
large marijuana growing operation; 2) Richard Davis had
passed through a locked electric gate to access the property;
and 3) that Richard Davis was related to the owners of the
property.

   [11] Based on these facts, the officers reasonably suspected
that Richard Davis was involved in the marijuana operation.
Unlike the defendant in Ybarra, the frisk of Richard Davis did
not occur in a public place to which he was not connected.
“Common sense suggests that there is a much greater likeli-
hood that a person found in a small private residence contain-
ing drugs will be involved in the drug activity occurring there
than an individual who happens to be in a public tavern where
the bartender is suspected of possessing drugs.” United States
v. Reid, 997 F.2d 1576, 1578-79 (D.C. Cir. 1993) (citing
Ybarra, 444 U.S. at 91); see also United States v. Ridge, 329
                    UNITED STATES v. DAVIS                  7775
F.3d 535, 541 (6th Cir. 2003) (reasoning that because officers
were searching a suspected methamphetamine lab, they could
reasonably infer that a customer or distributor would arrive on
the premises (citing Bohannon, 225 F.3d at 617)). Because
officers reasonably suspected that Richard Davis was
involved in narcotics activity, it was also reasonable for them
to suspect that he might be armed. See United States v.
$109,179 in United States Currency, 228 F.3d 1080, 1086
(9th Cir. 2000) (concluding that “[b]ecause the police reason-
ably suspected [ the defendant] of dealing in narcotics, it was
not unreasonable to believe that he might be armed”). Thus,
the officers permissibly frisked him for weapons.

   Although Terry does not allow “any search whatever for
anything but weapons,” Ybarra, 444 U.S. at 93-94, if, during
the course of a lawful patdown, an officer feels an item he
recognizes as contraband or evidence, the officer may seize
the item. See Minnesota v. Dickerson, 508 U.S. 366, 375-76
(1993). However, the “incriminating character” of the item
must be “immediately apparent.” Id. In Dickerson, the
Supreme Court held that the crack cocaine seized from a
defendant’s pocket was the product of an unlawful search
because the officer had already determined that the defen-
dant’s pocket did not contain a weapon when he “squeez[ed],
slid[ ] and otherwise manipulate[ed] the contents of the defen-
dant’s pocket” to determine the item’s incriminating charac-
ter. Id. at 378 (internal quotation marks omitted).

   In a situation similar to the one presented here, we held that
a small box containing ammunition should have been sup-
pressed when it was discovered by a patdown which exceeded
the “strictly circumscribed limits of Terry.” United States v.
Miles, 247 F.3d 1009, 1015 (9th Cir. 2001) (internal quotation
marks omitted). In Miles, while performing a Terry patdown,
an officer felt a small box about one-half the size of a package
of cigarettes. Id. at 1014. The record did not indicate that the
officer immediately recognized the box as contraband. Id. at
1014-15. Rather, the officer impermissibly continued to
7776                    UNITED STATES v. DAVIS
squeeze and manipulate the box, at which point, he deter-
mined that it contained ammunition. Id. at 1015.

   [12] Here, the record is not detailed as to the circumstances
surrounding the frisk of Richard Davis. What is apparent from
the record is that, during the frisk, officers discovered a tin
containing hashish oil. As in Miles, nothing in the record indi-
cates that officers immediately recognized the tin’s incrimi-
nating character during the patdown. Thus, any further
manipulation of the tin was impermissible. See id. at 1015.
There is nothing inherently incriminating about a tin container
and nothing in the record suggests that there was anything
special about this particular tin. Thus, the scope of the frisk
violated Richard Davis’s Fourth Amendment rights and the
district court erred by failing to suppress the hashish oil.3
However, the error does not mandate reversal. As described
below, the officers had other evidence, unrelated to the hash-
ish oil, that was sufficient to establish probable cause to
search Richard Davis’s truck. Any error by the district court
in failing to suppress the hashish oil was harmless.
  3
    We reject the government’s argument that it permissibly searched
Richard Davis pursuant to the search warrant for 2010 Stewart Road,
which provided for a search of “all other persons or occupants found to
be keeping, visiting, or frequenting” the premises of the property. The
warrant did not mention Richard Davis by name or contain any specific
factual basis giving rise to a fair probability that contraband or evidence
would be found on his person. See Greenstreet v. County of San Bernar-
dino, 41 F.3d 1306, 1309 (9th Cir. 1994) (“A search warrant designating
more than one person or place to be searched must contain sufficient prob-
able cause to justify its issuance as to each person or place named there-
in.”) (internal quotation marks omitted). The good faith exception of
United States v. Leon, 468 U.S. 897 (1984), which allows officers, in some
circumstances, to rely on the terms of the search warrant does not apply
here. The affidavit supporting the warrant could not “create disagreement
among thoughtful and competent judges as to the existence of probable
cause” as to Richard Davis. Id. at 926.
                    UNITED STATES v. DAVIS                 7777
                              D.

   Richard Davis also argues that the district court erred by
failing to suppress evidence found after officers searched his
vehicle. Although the Fourth Amendment generally forbids
warrantless searches, the warrant requirement is subject to
several well-established exceptions. One of these is the so-
called “automobile exception.” See, e.g., California v.
Acevedo, 500 U.S. 565, 569 (1991). The automobile excep-
tion permits police to search a vehicle as long as the vehicle
is “readily mobile” and “probable cause exists to believe it
contains contraband.” Pennsylvania v. Labron, 518 U.S. 938,
940 (1996) (per curiam). Therefore, we must determine
whether officers had probable cause to believe that Richard
Davis’s truck contained contraband.

   “Probable cause exists when, under the totality of the cir-
cumstances, ‘there is a fair probability that contraband or evi-
dence of a crime will be found in a particular place.’ ” United
States v. Luong, 470 F.3d 898, 902 (9th Cir. 2006) (quoting
Illinois v. Gates, 462 U.S. 213, 238 (1983)). Probable cause
determinations may be based in part on reasonable inferences.
United States v. Gourde, 440 F.3d 1065, 1071 (9th Cir. 2006)
(en banc).

   Because we hold that the hashish oil discovered on Richard
Davis’s person should have been suppressed, we must
exclude it from our probable cause analysis. Apart from the
hashish oil, the officers knew that: 1) Richard Davis accessed
an electronic gate and drove his pick-up truck onto the prop-
erty at 2010 Stewart Road; 2) the property at 2010 Stewart
Road was home to a large marijuana growing operation, con-
tained bulk quantities of processed marijuana, and numerous
firearms; 3) Richard Davis readily admitted to knowing “ev-
erything” about the marijuana operation; and 4) Richard
Davis also admitted that he “helped” with the marijuana oper-
ation.
7778               UNITED STATES v. DAVIS
   [13] Based on this information, officers could have reason-
ably inferred that there was a “fair probability” that Richard
Davis’s vehicle contained contraband. Richard Davis not only
knew about the marijuana growing operation, but participated
in it. Given that the marijuana growing operation involved a
large number of firearms, as well as large quantities of drugs
and cash, it was not at all unreasonable for officers to infer
that there was a “fair probability” that some or all of those
items were in Richard Davis’s vehicle during his visit to the
drug operation. Accordingly, the officers’ search of Richard
Davis’s vehicle was authorized by the “automobile exception”
to the Fourth Amendment’s warrant requirement. The district
court thus did not err by refusing to suppress the evidence
found as a result of the search of Richard Davis’s vehicle.

                             E.

   [14] Finally, Richard Davis argues that the district court
should have suppressed the evidence found as a result of the
search of his property located on Lower River Road. Officers
used the evidence found in Richard Davis’s vehicle, along
with his statements to Agent Wright, to obtain a warrant to
search the Lower River Road property. Richard Davis chal-
lenges the search of the property only on the basis that the
warrant was tainted because both the search of his vehicle and
his statements to Agent Wright should have been suppressed.
However, this argument is foreclosed in light of our holding
that neither the evidence found in Richard Davis’s vehicle nor
his statements to law enforcement officers should have been
suppressed. Accordingly, the evidence obtained under the
search warrant for the property on Lower River Road is not
“fruit of the poisonous tree.” See Wong Sun v. United States,
371 U.S. 471, 487-88 (1963).

                             V.

 In conclusion, the district court’s denial of Jeffrey Davis’s
motion to suppress is affirmed. The observations law enforce-
                    UNITED STATES v. DAVIS                 7779
ment officers relied upon to obtain the search warrant for
2010 Stewart Road were made outside the curtilage of the
Davis’s home.

   The district court’s denial of Richard Davis’s motion to
suppress is affirmed. Even without the tin of hashish oil, there
was ample probable cause to justify the search of both Rich-
ard Davis’s truck and his home. Because any error was harm-
less, the district court properly denied Richard Davis’s
motion.

  AFFIRMED.
