Urban Bee Diversity in a Small Residential Garden in Northern California

2009·6.9 MB·

by  Gordon W Frankie

U\^l RES.
J.
\-ol. 18(2), 20O9, pp. 368-379
Urban Bee Diversity in a Small Residential Garden in
Northern California
Gordon \V. Fraxkie, Robbix \V. Thorp, J.\ime C. Pawelek, Jexxifer Herxaxdez axd
rollix co\tlle
(GWT, JCP, RC) College of Xatuial Resources, Universit}' of California,
Berkele}-, California 94720
(RWT) Department of Entomolog}', Universit}' of California, Da\'is, California 95616
(RC) Pri\'ate entomological consultant, bee biologist, nature photographer
—
Abstract. Bee species di\'ersit\" is kno^vn to be high in numerous urban areas ^vorldwide. In
California our research group from the Uni\'ersit}' of California at Berkeley and Da\is has been
conductingsur\-eys state^vide ofurbanbee species andtheirpreferredhostplanttlo^vers since 2005
and find that manv cities also have high species diversit}'. In this paper we examine in some detail
the bee-flower relationships in one small residential garden in northwestern California - Ukiah in
Mendocino Co. In this garden, which is densely packed with preferred bee plants, we ha\-e
recorded 68bee species; cit\^vide,Ukiahhas 91 recorded species. Highbee diversit}^ inthe garden
is behe\'ed to be related to the high diversit}- and abundance of plant materials that provide a
continuous source ofpollen and nectar during the entire grooving season. Bee visitation counts on
selective (target)plantt}'pesindicatethebee-flowerrelationships arerelati\-elypredictable,andthis
information can be used to plan and estabhshbee habitat gardens.
Studies on diversit}' of bee species in to^vards recognizing interesting and desir-
urban environments ^vorld^vide have been able urban fauna and how to encourage
increasing in recent years (see revie^vs in and enjoy these organisms that frequent
Cane 2005; Hernandez et al. 2009b). Some and establish in our gardens (Hayes 2003;
of these studies have undoubtedly resulted Carroll and Salt 2004; Stone and Barlo^v
from research to document more of Earth's 2005; Louv 2008; Tallamy 2009; Erankie et
biodiversity', even in environments that al. 2009).
have been severely disturbed by human The Universit}' of Cahfomia at Berkeley
activities and development. Increasing also and Davis have been surveying urbanbees
are popular and semd-technical publica- in Califomia since the late 1990s with the
tions that provide objective biological general goal of increasing knowledge
profiles on the wide variet}' of organisms about a group of common insects thathave
that U\-e with us in the ever-expanding cit\' estabUshed ecological relationships ^vith
environments (Grissell 2001; Low^r}^ 1999, gardens and have gone largely unnoticed,
2007; Taflamy 2009). In an earUer and until recently, \vhen the value of all bees
relevant volume, Owen (1991) produced became better known through Colony
an extraordinar}' account of 15 sequential Collapse Disorder (CCD) of our important
years of documenting the biodiverse or- honey bees (XRC 2007). Since 2005 our
ganisms that came to visit her small research group has focused on a statewide
residential garden in Leceister England. sur\-ey of urban bee diversity' and ecology,
She also points out the significance of especially with regard to preferred orna-
gardens for conserving wildlife. Thus, mental host flow^ers. The first paper on this
there is a definite new trend or movement work (Erankie et al. 2009) provides an
Vc: \_ .czE? 2,2009 369
oveniew" of our findings through 2007. As ontheorganic gardenattheFetzerwinery
this work continues it is clear that urban innearbyHopland(—16 kmSSEofUkiah).
areas can support a rich assortment ofbee Fortuitously, most of the selected plant
sf>eciesiftherightfloralandotherresourc- t\-pes are attractive to local bees.
es are present ''Ahme et al. 2009). TheUTciah garden^sas Hkemostgardens
In this paper .••e rresent findings from in urban California, that is, d\TLamic with
one of the garder^ z^. the cit\- of Ukiah, some plants progressively added and
Mendocino Co. :in north^Testem California others removed over the period 2005-
^vhere there is rich diversit\^ of plants and present. Most plant t\-pes ^sere perennial
native bee species. Goals of this paper are and planted on a thick laver oftopsoilthat
first, to exainine in some detail the floral was originally brought to the earden in
relationships o: garden plants (origin, 2004. The closest natural area is 4004-
flo^^ering seas:r r :^er nectarresources) meters to the west ^sTiere houses stop at
to local native Caliicn^ia bee species over the edge of an extensive and dense oak-
the period 2005 through 2008. Second, to ^Noodland habitat tiiat occurs or. a steep
compare the bee findings of the study movmtain hillside. Important bee plants
gardenwithbeetotalsforther—estofUkiah. such asArbutus inenziesiiPursh andseveral
Sitedescription: UJdahGarden, ^Thecit\"of A :::5::: :y.:5 ard Zeanothus species are
Ukiah (pop. 15,497, as of 2000; elevation '. liel'. scattered in this habitat Open
—186 m) is located in Mendocino Co. in r.d is rare on the hillside. Westward
northwestern California in a la-ge valley ^sithin a kzr. he study garden are a few
surroundedbyIo^n elevationmountains(iq> small, scattered patches of chaparral veg-
to—1,065 minelevation).Mostofthedtyis etation; within two km are larger patches.
in the western half of the valley, including About five km east of Ukiah is the
the study garden. The eastern half of the Ma\acmas Range of mountains that is
valley is largely agricultural with pear predominated with well developed and
orchards and vineyards. Almost all houses diverse chaparral vegetation. The entire
ar ~ rariens in Ukiah can be considered ^sildareaaroundUkiahisfilledwithmany
res:acr.-al, and in most lots land has been native ^sildflower spedes (Steams 2007).
clearedandhousesandgardensestablished. Thie ir.air_ par: of the Ukiah garder. v.cs
Because Ukiah is inland and somewhat south fadng in the front of the house and
m
isolated b\^ mountains, summers are hot measured -100 m- (10 X 10 m). Two
anddry,butwithcoolevenings.Wintersare path^vays traversed the garden and met at
mildtocoldwitiioccasionalperiodsoffrost afrontgate. A smallnarrows'strip ofgarden
andfreezingtemperatures,whichhaslimit- was located on the east side oi the house,
ed the use of some ornamental plant ^\hichmeasured —20 m-. Thevastmajority
materialsinthe area ofbee plants were found in the frontyard.
Asin almostever\' Califomia dt}", urban Plants in both tiie front and side yards
residentsinUkiahuse ahighpercentage of received regular ^vatering, pruning, and
non-nativeplantmaterialsintiieir gardens ^Needing. In the front yard plants were
(Frankie et al. 2005, 2009). In tiiis regard, packedtightiyinthisrelativelysmall space
tiie study garden is no exception as about (Fig. 1).Plantsinthesideyard^nere sraced
75% of its ornamental plants are non- more ^\idelv.
natives (Table 1). The garden is unique, \L\TERL\L5 -\XD METHODS
however, in that it contair^s a relatively
highdiversity ofplantmaterials compared Bee and plant surveywork at the UTdah
tootherssurveyedthroughoutthedty. The garden^sas initiated duringthe summerof
garden ^nas first planted in 2004, and 2005; three ^"isits ^vere made that year, hi
selection oi ornamental rlants ".'.as based subsequent years \isits ^vere made se^ eral
370 Journalof Hymenoptera Research: Festschrift Honoring Roy Snelling
times during the entire growing season: survived only one season. These species
2006 (9 visits), 2007 (13), and 2008 (12). Bee were not adapted to the cold temperatures
collections and bee frequency counts were that occur during winter in Ukiah.
made each year.
RESULTS
Voucher bee species were collected with
aerial nets from all garden flowers that We recorded allplanttypes (55) found in
showed attraction to bees. Collected bees the garden that showed attraction to bees
were transported to the lab atUC Berkeley, over the period of 2005-2008 (Table 1).
curated and sent to thebee lab atUC Davis There were a very few others that did not
to be identified by R. Thorp. Records of attractbees (e.g. ornamental grass) or were
identified bees are kept on file inboth labs; non-reproductive; all ofthesewere small in
curated bees are permanently housed at size and not recorded. As indicated in
UC
Berkeley. Table 1, bees were attracted to plants in 19
Bee frequency counts were made on different families with Asteraceae and
selected (target) plant types in order to Lamiaceae having the greatest number of
trackbee diversity and abundance through representative species (15 each). Members
time (see coded plants in Table 1). Patches of these two families together represented
m
(—1-1.5 square) of target plant types in almost 55% of the plant types in the
good flower were observed for three- garden. Frankie et al. (2005) also found
minute periods, and each bee that made plants in these two families to be the most
contactwith reproductive flower parts was important sources of pollen and nectar in
counted. Once counted on the first flower two San Francisco Bay Area cities.
visited, they were not counted again, The 55 plant types listed in Table 1
which allowed for focus on any newbee(s) consisted of 14 California natives (25%)
entering the patch. Numerous bee counts and 41 non-natives iJ5%). Together they
were made on target plants during each provided pollen and nectar forbees during
year when the main bloom period oc- each month ofthe year (Wojcik et al. 2008).
curred. Some bee taxa could be identified Further, many of the plants have long
on the flowers, whereas others had to be flowering periods, some of which spanned
collected to confirm identification. Counts two seasons. Examples of these included
provided bee diversity and abundance Bidens ferulifolia DC, Coreopsis grandiflora
measures that were tallied and averaged CVS, Cosmos bipinnatus Cav., Erigeron glau-
for each plant type (Frankie et al. 2005, cus Ker Gaw., and Solidago californica Nutt.
2009). In this paper we focus on bee for pollen and nectar, and Lavandula sp. 2,
diversity measures. Future papers will be Nepeta X faassenii Bergmans, Perovskia
concerned with abundance measures for atriplicifolia Benth., Salvia uliginosa Benth.,
the study garden and the entire city of and Linaria purpurea (L.) Mill, for nectar.
Ukiah. This resource continuity, which results in
Most target plants chosen in this study several plant types being in flower simul-
were the same ones used in an ongoing taneously, isbelieved tobe one ofthe main
statewide survey of urban bees and their factors sustaining diverse bee species dur-
host flowers (Frankie et al. 2009). Because ing the growing season.
several target plants were either missing or Bee taxa collected at the Ukiah garden
in limited numbers, we added these plants from2006 through2008 arelisted inTable 2.
in 2007 and 2008 to record bee activity (see To date, 68 species in 26 genera and five
coded plants in Table 1). Most added families have been recorded, with most
plants provided useful information, but a species in the families Megachilidae (32)
few such as Encelia californica Nutt., Salvia and Apidae (19). Collections of bee species
Tndigo Spires', and Duranta erecta L. increased during each year (30, 40, 53
Volume 18, Number2, 2009 371
respectively),andthiswasrelated,inpart,to Cresson, although rarely collected, was
morevisitsmadein2007/2008than2006and also a summer bee.
totheaddedbee-attractiveplants duringthe Numbers of plant types visited by each
latter two years (Table 1). The overall list of bee species were compiled and sorted to
bee taxarecorded fromthis and otherUkiah California natives and non-natives (Ta-
gardens for the study period was 91 species ble 2). We also arbitrarily divided the bees
in 28 genera and five families. into two groups: species that visited
—
Bee seasonality. Many of the bee species relatively few host plant types (1^ natives
had seasonalpatterns ofoccurrence,thatis, plus non-natives), and those (5 and above)
spring, summer, or both seasons (Table 2). that had a wider host range. In the first
Additional ongoing collections are consid- group there were 54 bee species and the
ered necessary for characterizing more vast majority of them (41) were collected
precisely the seasonality for most species, on only one or two hosts. The second
however, some patterns are presented here group had 15 species, which included aU
that are well known for selected genera/ four of the introduced species. Apis melli-
species in northern California. fera Linnaeus, Hylaeus punctatus (BruUe)
There were several groups of spring- (Colletidae), Megachile apicalis, and M.
season bee taxa (Table 2). The most prom- rotundata. As expected the host range of
inent groups were in the genera Andrena A. mellifera was the highest with 21 plant
(Andrenidae) and Osmia (Megachilidae). types visited, followed by M. rotundata
The twoAndrena species,A. auricoma Smith with 12 host types. The three California
and A. cerasifolii Cockerell, were exclusive- native bee species with the widest host
lyspringbees, and 10 of 12 recorded Osmia ranges were Halictus ligatus Say (Halicti-
species were spring bees. One of 12 Osmia dae) (10 plant types) and two apids,
was a spring/early summer species; Osmia Xylocopa tabaniformis orpifex Smith (9 types)
regulina Cockerell was a summer bee. In and Ceratina acantha Provancher (8 types).
the Apidae, Anthophora californica Cresson, It is noteworthy that California native bees
Eucerafrater albopilosa (Fowler), and Habro- in the second group (11 of 15 species) were
poda depressa Fowler are wellknown spring collected more frequently (10 of 11 species)
bees. Bombus species (4) are primitively on non-native host pl—ants.
eusocial and thus multiple seasonbees,but Plant-bee relations. Some plant species
most were in relatively high abundance had an unusual capacity to attract highbee
during this period. Although three of four diversity. We examined this capacity in
species were also collected in summer, native and non-native plant types having
their frequencies were substantially lower. the greatestbee diversities (Table 3). In the
This is probably due to the fact that two natives, Carpenteria californica Torr., Solida-
species (B. melanopygus Nylander and B. go californica and Erigeron glaucus had the
vosnesenskii Radoszkowski) starttheir nests highest bee species diversities. In non-
in January and peak in early spring. native plants, bee species counts were
The most prominent group of summer higher than natives in four of five plant
bees was in the genus Megachile (Mega- types. Most attractive non-natives are
chilidae). Seven of nine Hsted species were nectar resources in the Lamiaceae. Except
collected in summer. Two of the nine, M. for C. californica, which has a relatively
apicalis Spinola and M. rotundata (Fabri- short flowering period (May), the long
cius), whichwere introduced in California, blooming periods of the other nine plants
were found duringboth seasons. Only one (Table 3) allowed them to be exposed
species, M. lippiae CockereU, was collected longer to a greater diversity ofbee species.
in spring. In the Apidae, Melissodes robus- AU but C. californica bloomed for at least
tior Cockerell was a summer bee; M. lupina three months. This phenological character-
372 Journalof H^^iexopter.a Research: Festschrift Hoxorixg Ro\ Sxellixg
Table1. PlantsattractingbeesintheUkiahstudygardenfrom2005-2008.PlantnamesaccordingtoHickman
(1993) and Brenzel (2007). Cultivars = cvs.
Plantspecie?orcultivars{c\s' PlantOrigin Flo%\-eringPeriod- FloralReward'
Apiaceae
Enmgium Non-Nat Sum N
sp.'^
Asteraceae
Achillea millefolium L/ Nat Spr-Sum N/P
Achillea 'Moonshine' Non-Nat Spr-Sum N/P
Aster X frikartii^- Non-Nat Sum-Fall N/P
Bideiis fendifolia DC.'~" Non-Nat Spr-FaU N/P
Centaiirea cineraria Pall. Non-Nat Spr-Sum N/P
Coreopsisgraiidiflora -2 cvs"*~ Non-Nat Sum N/P
Cosmos bipimmtus Cav."*-'' Non-Nat Sum-Fall N/P
Cosmos sulphureus Cav/~ Non-Nat Sum-Fall N/P
Encelia califomica Nutt." Nat Spr-FaU N/P
Erigeronglauciis 'Wa)'ne Roderick'^-' Nat Spr-Sum N/P
Erigeron karcinskianus DC.-^ Non-Nat Spr-Fall N/P
Gaillardia X grandiflora Hort.^ Non-Nat Spr-Fall N/P
Grindelia hirsutula Hook. & Am.^ Nat Spr-Sum N/P
Solidago califomica Nutt.-^ Nat Sum-Fall N/P
Bignoniaceae
Campsis radicaiis (L.) Seem. Xon-Xat Spr ?
Boraginaceae
Echium zcildpretii H.Pearsonex Hook.f. Xon-Xat Spr N/P
Brassicaceae
Lobularia maritima Desv. Xon-Xat Spr-Sum N
Buddlejaceae
Buddleja davidii Franch. Xon-Xat Sum N
Crassulaceae
Sedum sp. ?Xon-Xat Sum N
Fabaceae
Wisteria sinensis S\veet-^ Xon-Xat Spr N
Iridaceae
Sisyrinchium helium S.Watson Nat Spi N/P
Lamiaceae
Calamintlia nepetoidesJord."* Xon-Xat Sum-Fall N
Lavandula stoeclias L.^ Non-Nat Spr-Sum N
Lavandula - sp. 2'' Non-Nat Spr-Fall N
Lavandula - sp. 3- (white flowers) Non-Nat Sum N
Nepeta xfaasseniiBergmans- Non-Nat Spr-Fall N
Perovskia atriplicifolia Benth.' Non-Nat Sum N
N
Salvia apianaJeps. Nat Spr
Salvia brandegeeiMunz Nat Spr N
N
Salviaclevelandii(A.Gray)E.GreeneorS.leucophyllaGreene Nat Spr
Salviagreggii (2cvs)^ Xon-Xat Spr-Fall N
Salvia 'Indigo Spires'^-^ Xon-Nat Spr-Fall N
Salvia uliginosa Benth.^^ Non-Nat Sum N/P
Salviaguaranitica A.St.-Hil. ex Benth. Non-Nat Sum N
Teiicrium x lucidrys Boom (7. cliamaedrys L.) Non-Nat Sum N
Liliaceae
Allium sp. Non-Xat Spr N
Onagraceae
Epilobium canum (Greene) P.H. Ra\-en Nat Sum N
Gaura lindlieimeriEngelm. & Gra\" Non-Nat Sum N
Philadelphaceae
Carpenteria califomica Torr. Nat Spi
Volume 18, Xumber2, 2009 373
Table 1. Continued.
Plantspedesorcultivars(cvi PlantOrigin no^'.'erir.gPeriod- FloralRe^vaxd'
Plantagmaceae
Ajitirrhimim majus L. Xon-Xat Spr ?N/P
Polygonaceae
EriogonumgrandeGreen \-ar. rubescens Xat Sum N
Munz
Eriogonum imihellahim Torr. Xat Spr-Sum N
Ranimculaceae
Aquilegm sp. Xon-Xat Spr N
Rutaceae
Rutagrareolnis L. Xon-Xat N
Scrophulariaceae
Luiariapurpurea (L.) \Iill.'~ Xon-Xat Sum-Fall N
Penstemon digitalis 'Husker'sRed' Non-Xat Spr N
Paistemon 'Midnight' Xon-Xat Spr N
Penstemon sp. (red flower) Xon-Xat Spr N
Penstemon JieteropJiyUus S.Watson^ Xat Spr N
Verbenaceae
Aloysia triphylla Royle Xon-Xat Sum N
Duranta erecta\^.~ Xon-Xat Simi N
Verbena bonariensisL. Xon-Xat Sum N
Total: 55types (includes allcultivars)
'Xat- Californianative plant; Xon-Xat-notnative to California flora
-Spr- Spring; Sum- Summer;Fall
-X-Xectar;P- Pollen
^Plants progressivelyadded to garden overperiod 2006-2008
^Bee frequencvcounts were collected onthese targetplants
istic coupled Avith their inherent attraction among simultaneously flo^vering t}'pes in
(Frankie et al. 2005, 2009) probably ac- relatively different and predictable pat-
counts for part of the higher diversit}' terns (Frankie et al. 2009). Xumerous bee
levels. frequencv counts that have been gathered
A relationship between flo^ver patch size over three years of m.onitoring exemplify
and bee diversit}' ^vas also suggested from how summer flo^vering Solidago califomica,
results presented in Table 3. It appears that Erigeron glaucus, and Perorskia atriplicifolia
large patch size of some bee-attractive attracted different bee groups during coin-
plant t\^es may attract high bee diversi- ciding tloAvering periods. In descending
ties. In the case of t^vo natives, Carpenteria order of occurrence, Solidago attracted
califoniica and Solidago califoniica, and the mostly halictids, then honey bees, non-
first four non-native plant t}~pes (Table 3), Os?nia megachilids, and Ceratina species.
all had patches of more than 1.5 m- of Erigeron attracted non-Osmia megachilids,
tlowering space. Frequency counts in sub- halictids, and Ceratina. Perovskia attracted
patches (—1-1.5 m-) in all but Caiyenteria mostlv honey bees, then non-Osrriia mega-
califomica (Table 1) ^vere used to determine chilids, and Ceratina species (Fig. 2). Xepeta
the high bee diversities in each of these X faassenii, \vhich flowers extensively in
selected species. Experimental studies ^vill both seasons attracted honeybees, Ceratina
be needed in the future to further examine species, and non-Osmia megachihds in the
this relationship. summer, but in spring the same Xepeta
Many plant types tlowered simulta- plants attracted somewhat different bee
neoiisly during any given time period. species and frequencies: honey bees, Bo?7t-
The seasonal bee species sort themselves hiis species, and Osmia species. Thus, on a
374 Journalof Hymenoptera Research: Festschrift Honoring Roy Snelling
Fig. 1. Ukiah study garden duringa springbloom.
given summer observation day, when all mento and La Canada Flintridge (near
four plant types are in flower, one can Pasadena).
expect certain frequencies of bee taxa on
one plant type and different sets on the Ukiah Garden versus Greater Ukiah
other three host plant types. Four bee taxa in the Ukiah garden were
Simultaneous flowering of several spe- compared and contrasted with the same
cies had another behavioral-ecological ef- taxa from collections made in other gar-
fect that was first observed during the dens throughout the city of Ukiah where a
survey of bee-attractive plants in two San total of 91 species have been recorded to
Francisco Bay Area cities from 1999-2003 date. Thesetaxawere selectedbecausethey
(Frankie et al. 2005). Some plant species provide insight on host plant factors that
thatare usuallyunattractive tobees such as maybe responsible for the extantbee list at
Achillea millefolium L., Erigeron karvinskia- the Ukiah—garden.
nus DC, and Verbena bonariensis L. become Osmia. Osmia species are well repre-
attractive when diverse and attractive sented with 12 of the 15 city species found
flowering species surround them. Appar- in the garden. The most important host
ently,bees will try outthese plantsbecause plants in the garden were Lavandula sp. 2,
of their close proximity to attractive plants. Linaria purpurea, and Nepeta X faassenii.
Once tested, these ''unattractive plants'' Citywide, Osmia were also found on
become attractive. We have observed this Phacelia tanacetifolia Benth.
—
phenomenon previously in other surveyed Andrena. Only two of 10 city species
California gardens, for example, in Sacra- were found in the garden. Examination of
,
VOLLAIE IS. Xlaser2, 20Q9
host records clearly indicates that Andrma rightplantt}^es flo^veringinsequence over
species not found in the garden ^vere a grooving season can result in high bee
associated ^vith mostly California natives: diversit}' in the Ukiah area.
Ceanothus species and Arbutus meiiziesii This relationship of preferred high plant
neither of ^vhich are in the garden. One of diversity- to high bee diversity- ^vas also
the city Andreim species ^vas found on demonstrated at the Universit}^ of Califor-
flo^vers of the non-native Philadelphus nia, Berkeley Oxford Tract where in 2003/
coroiiarius L. (s^veet mock orange). Other 2004 a specially constructed garden ^vas
researchers have also noted a scarcit}' of designed to provide preferred poUen and
Andreim in urban gardens (Antonini and nectar of ornamentals to local native bees
Martins 2003; Fetridge et al. 2008). for the entire grooving season OVojcik et al.
Agapostemon texaniis Cresson is one of 2008;Hernandez etal. 2009a). Atthe end of
the most common bee species found on a the grooving season in 2004, the plants had
variet}' of urban host plants in California attracted 37bee species (Hernandez2009a).
(Frankie et al. 2009), ho^ve\"er, we ha\e ^et Additional sampHng since then has added
to collect it in the Ukiah garden. In greater sevenmore species to theKst (R. Thorp and
Ukiahit^vas onlycollected once onchicor\' }. Hernandez,pers. com.). Other gardens in
flo^vers. — the state (Frankie et al. 2009) that fortu-
Lasioglossiwi. Onlv five species ^veie itouslyprovide preferredbeeplants during
found in the garden, yet 12 species have the grooving season are found in Sacra-
been collected throughout Ukiah on plants mento (Masonic LawTi Cemeter\' %vith 69
of Ceanothus sp., Eschscholzia californica bee species) and La Canada FLintridge
Cham., Ceanothus Julia Phelps', Convolvu- (Descanso Gardens ^vith 94 bee species).
lus arvensis L., and Centaurea solstitialis Most sur\eyed urban areas in California
Asso. Xone of these plant t}-pes ^vere in have diverse floral resources that diverse
the study garden. native bees need for reproduction and
survival (Frankie et al. 2009). There are a
DISCU5SIOX COXCLUSIOXS
-.-VXD fe^v urban areas, ho^vever, ^vhere the right
Although the study garden had a high plantt}~pesfornativebeesarescarce,^\Tdely
diversit}'ofbeespecies,numberscouldhave scattered, or nonexistent, and this pattern
been higher if more aggressive sampling seems to reflect local gardening practices
methods had been used, for example pan and plant selections (B. Ertter, UC Berkeley
traps fWojdk et al. 2008; Hernandez 2009b), JepsonHerbarium, pers. com.). Inthese few
vane traps (R. Thorp pers. com.), and ^\ith urban areas, ^vhich include the cities of
earUer season visits (Feb./Mar.) and more Monterey-Carmel-Padiic Grove, Paso Ro-
frequent monitoring inter\'als of ever\^ two bles,andSanI>iego,preferredbeeplantsare
to three ^veeks. Further, if more host plants scarce and^videlyscattered as arethenative
of other bee species ^vere added, it ^\'Ould bee species (G. Frankie, unpub.).
alsoprobabh'increasebee spedes diversity'. In the case of Ukiah and other California
In this regard, adding Ceanothus shrubs or cities, mostplants used in gardens are non-
Arctostaphylos species to the garden ^vould natives to the state. Although native
likely result in more Andrena species to the California bees coevolved ^vith certain
former and increased abundance of Bombus native plants, many have the capacity- and
and Ajithophora species to the latter. Ceano- tlexibilit}' to use a variety of plants,
thus 7ulia Phelps' and C. T)ark Star' %\ere including some non-natives. A preliminary
justadded inTune2009, andt^voArctostaph- sur\'ev of native versus non-native bee
ylos speciesinanadjacentfallo^vedlottothe plants in Berkeley revealed that of the
study garden are scheduled for monitoring 1000- plant t^-pes used in this cit\', onlv
in early 2010. Thus, high diversit\- of the —50 ^vere natives; —950 ^vere non-natives.
376 Journalof Hymenoptera Research: Festschrift Honoring Roy Snelling
Table2. Listofbee taxa collected atUkiah garden from 2006-2008. Numbers ofCalifornia native and non-
native plant types visited by eachbee species are listed respectively in parens.
Beespecies BeeSeason'
ANDRENIDAE
Andrma auricoma Smith (1,1) + Spr
Andrma cerasifolii Cockerell (1,0) + Spr
APIDAE
AntJiophora californica Cresson (0,1) + + Spr
Anthophora urbana Cresson (0,1) + + + Spr/Sum
Apis mellifera Linnaeus^ (5,16) + + + Spr/Sum
Bomhus californicus Smith (0,1) + Spr
Bo77ibusflavifrons Cresson (1,3) + + + Spr/Sum
Bomhus melanopygus Nylander (1,4) + + Spr/Sum
Bomhus vosnesenskiiRadoszkowski (0,3) + + Spr/Sum
Ceratina acantha Provancher (2,6) + + + Spr/Sum
Ceratina nanula Cockerell (1,3) + + + Spr/Sum
Ceratina sequoiaeMichener (0,1) + + Sum
Ceratina tejonensis (1,3) + + + Spr/Sum
Eucerafrateralbopilosa (Fow^ler) (0,1) + + Spr
Habropoda depressa Fowler (0,2) + + Spr
Melissodes lupina Cresson (1,0) + Sum
Melissodes robustiorCockerell (0,6) + + + Sum
Melissodes tepida timberlakeiCockerell (1,3) + + + Spr/Sum
Nomada sp. CM (0,1) + Spr
Nomada sp. F (1,0) + Spr
Xylocopa tabaniformis orpifex Smith (1,8) + + + Spr/Sum
COLLETIDAE
Colletes kincaidiiCockerell (1,0) + Sum
Hylaeus episcopalis (Cockerell) (0,1) + Spr
Hylaeus mesillaeCockerell (3, 6) + + + Spr/Sum
Hylaeus polifolii (Cockerell) (1,2) + + Sum
Hylaeuspunctatus (Brule)^ (5,0) + + + Spr/Sum
Hylaeus verticalis (Cresson) (0,1) + Sum
HALICTIDAE
Halictusfarinosus Smith (2,4) + + + Spr/Sum
Halictus ligatus Say (4,6) + + + Spr/Sum
Halictus tripartitus Cockerell (3,4) + + + Spr/Sum
Lasioglossum incompletus (Craw^ford) (1,0) + Sum
Lasioglossum tegulariformis (Crawford) (1,2) + Spr/Sum
Lasioglossum (Dialictus) sp. F (0,1) + Sum
Lasioglossum (Dialictus) sp. 2 (0,1) + Sum
Lasioglossum (Evylaeus) sp. (1,0) + Sum
Sphecodes sp. CM (1,0) + Sum
MEGACHILIDAE
Anthidiellum notatum robersoni (Cockerell) (0,1) + + Sum
Anthidium illustreCresson (0,1) + Sum
Anthidium placitum Cresson (0,1) + Sum
Ashmeadiella cactorum basalis Michener (0,1) + Sum
Ashmeadiella timberlakei solida Michener (0,1) + Spr
Coelioxys apacheorum Cockerell (0,1) + Sum
Dianthidium ulkei (Cresson) (3,2) + + Sum
Dolichostelis laticincta Cresson (0,1) + + Sum
Heriades occidentalis Michener (2,3) + + + Spr/Sum
Hoplitis productagracilis (Michener) (0,1) + Spr
Megachileangelarum Cockerell (0,4) + + + Sum
Megachileapicalis Spinola (0,5) + + + Spr/Sum
Megachilecoquilletti Cockerell (0,1) + Sum
Volume 18, Number1, 2009 377
Table 2. Continued.
Beespecies 2006 2007 2008 BeeSeason
Megachilefidelis Cresson (1,5) + + + Sum
Megachilefrugalis Cresson (0,3) + + Sum
Megachilegentilis Cresson (1,2) + Sum
Megachile lippiaeCockerell (1,0) + Spr
Megachile montivaga Cresson (0,1) + Sum
Megachile rotundata (Fabricius)^ (3,9) + + + Spr/Sum
Osmia aglaia Sandhouse (0,1) + Spr
Osmia calla Cockerell (0,1) + Spr
Osmia coloradensis Cresson (2,2) + + Spr
Osmia cyanella Cockerell (1,3) + + + Spr
Osmia densa Cresson (0,1) + Spr
Osmiagabrielis Cockerell (0,1) + Spr
Osmiagranulosa Cockerell (0,2) + + Spr/Sum
Osmia lignariapropinqua Cresson (0,1) + Spr
Osmia montana Cresson (1,0) + Spr
Osmia nigrifrons Cresson (0,1) + Spr
Osmia regulina Cockerell (1,2) + + Sum
Osmia sp. A (0,1) + Spr
Protosmia rubifloris (Cockerell) (2,2) + + Spr/Sum
Species Totals: 30 40 53
Totals for allyears: 5 families, 26 genera, 68 species
^Spr-spring;Sum-summer
^Introducedbee species inCalifornia
Further, about 80% of the natives attracted seasonal sequence of bee plants that pro-
bees at measurable levels, whereas slightly vide a continuum ofpoUen and nectar, and
less than 10% of the non-natives attracted 3) probably large flowering patch sizes of
bees. Still, this 10% amounted to -90 the most attractive plant types. Another
attractive plant types (Frankie et al. 2005). key factor is availability of nesting sub-
Further, many to most bee-plant relation- strates. Nesting bees have only rarelybeen
ships in Berkeley and most other gardens observed inthe Ukiahstudy garden, which
in the state are relatively predictable suggests that most species probably came
(Frarvkie et al. 2009). That is, certain bee from outside the garden. In a relevant
taxonomic groups can be expected to be paper. Cane (2005) calls attention to the
associated with given plant types, and this three needs of bees: floral resources,
predictability allows for planning of bee nesting opportunities, and ''condition of
gardens, which are now becoming more the urban matrix." In the case ofthe Ukiah
common in California and elsewhere (Pa- garden, condition of the urban (or envi-
welek et al. 2009). Other authors have also ronmental) matrix becomes all-important
commented on the value of using native as it appears that mostbees come from the
and non-native plants for pollinator gar- surroundingarea, whichprobablyincludes
dens (Fetridge et al. 2008). nearby wild areas.
A synthesis of findings in this study Finally, updates on the California state-
suggests that in the case of Ukiah and wide survey of urbanbee species and their
probably several other California cities, preferred plant types can be found at
planning for a highly diverse bee garden our website: http://nature.berkeley.edu/
will depend on several plant factors in- urbanbeegardens. More than 225 bee spe-
cluding: 1) high plant diversity of the right cies have been collected already from the
native and non-natives, 2) a complete surveyed cities of Redding, Ukiah, Sacra-