Thursday, March 23, 2017

A Mixed Bag of Bumblebee Plants for Vancouver Island (Natives and Exotics)



This list is a work of progress: check in for updates as I continue to organize this information. Also, consult with your local nursery to get the native species of the if at all possible.  Check out this blogpost for a short list of the top plants for bumblebees on the Island.

* Denotes a medicinal plant for bees
BOLD denotes special interest for bumblebee plants (buzz pollinated, longer corollas or special relationships, ie trip pollination)

Native and Near Native Shrubs: Willow (Salix spp.) maybe the most important plant for honeybees and significant for bumblebee queens, Red Osier Dogwood (Cornus sericea) is another good one for weavers, Snowberry (Symphoricarpos albus) also an essential bee plant because it blooms over a period of months, Black Twinberry (Lonicera involucrata) Loads of nectar, berries used for dye, Hairy Manzanita (Arctostaphylos columbiana)
June Gap: Ninebark (Physocarpus spp.) native species is Pacific Ninebark (Physocarpus capitatus), Spirea spp., native is Spirea douglassi, Mock Orange (Philadelphus lewisii), Native Roses
Edible/Drinkable Shrubs: Salmonberry (Rubus spectabilis), Oregon Grape (Berberis spp.), Kinnikinnik (Arctostaphylos uva-ursi), Blueberries (Vaccinium spp.),  Evergreen Huckleberry  (Vaccinium ovatum), Wood’s Rose (Rosa Woodsii), Prickly Rose (R. acicularis), Blueberry Vaccinium spp., Potentilla spp.
Sumac (Rhus spp.), Blue Elderberry (Sambucus cerulea), Currants (Ribes spp.) clove currant and red-flowering don’t plant European black currants, Raspberry (Rubus spp.) Thimbleberry (Rubus parviflorus), High Bush Cranberry (Viburnum trilobum), Labrador tea (Rhododendron groenlandicum),
Native and Near-Native Trees: Arbutus (Arbutus menziesii), Chokecherry, Crabapple the native is Pacific Crabapple (Malus fusca), Pincherry, Saskatoon, Western Mountain Ash (Sorbus scopulina)
Native Vines: Virgin’s Bower Clematis (Clematis ligustifolium) beware of invasive look-alikes, Trumpet honeysuckle (Lonicera ciliosa)
Exotic Trees: Redbuds (Cercis spp.), Hawthorn (Crataegus spp.), Linden (Tilia spp.) avoid silver linden (Tilia tomentosa); Stone Fruit Trees: apple, cherry, peach, apricot, pear, quince, and plum
Exotic Shrubs: Spirea spp., Climbing roses, Potentilla spp. important late-blooming shrub
Edible Native Perennials: Native violets, Nodding onion (Allium cernuum) and other native alliums
Early Shade-tolerant Perennials: Bleeding heart (Dicentra spp.) toxic, Solomon’s Seal (Polygonatum spp.), Canadian Columbine (Aquilegia canadensis) and other Aquilegia spp. toxic,  
Native and Near Native Perennials: Spring-gold (Lomatium utriculatum) an early-blooming umbel esp. important for short-tongued bees like the Western Bumblebee
Deltoid Balsamroot (Balsamorhiza deltoidea), Large-leafed Avens (Geum macrifolium) and other Geum spp.
Broad-leafed Shooting Star (Dodecatheon hendersonii), Milk Vetch (Astragalus spp.), Native Silvery Lupin (Lupinus argenteus) and other Lupinus spp., Blue-eyed Mary (Collinsia spp.), Broomrape (Orobanche spp.) Yellow Rattle (Rhinanthus minor), Native Larkspurs (Delphium menziesii ) HIGH toxicity warning
Penstemon spp., Canadian Milk Vetch (Astragalus Canadensis and other native spp.), Blue Gentian (Gentiana spp.), Monkey Flower (Mimulus sp.)
Camassia spp., Woodland Strawberry (Fragraria vesca), Yarrow (Achillea Millefolium), Potentilla spp. native species and cultivars are great, Common Harebell (Campanula rotundifolia and other native and exotic spp.),
Plains Prickly Pear (Opuntia polyacantha), Gumweed (Grindelia spp.), Rocky Mountain Bee Plant (Cleome serrulata), Anise Hyssop (Agastache foeniculum), Erigeron spp., Native Lilies (Erythronium spp.), Jacob’s Ladder (Polemonium spp.), Cranesbill Geranium (Geranium spp.)
Near Native Annual: Bienenfreunde aka Lacy Phacelia (Phacelia tanacetifolia) very important bee pasture plant for nectar and pollen—stagger-plant this throughout the growing season. Good for honeybees and bumblebees.
Late-Blooming Native and Near-Native Asteraceae: Joe Pye Weed (Eutrochium spp.) Blanket Flower (Gaillardia spp.), Tickseed (Coreopsis spp.), Pearly Everlasting (Anaphalis margaritaceae), Asters (Symphyotrichum spp.), Goldenrod (Solidago spp.), Coneflowers (Echinacea spp.), Coneflowers (Ratibida spp.), Black-eyed Susan (Rudbeckia spp.), Gold Star (Crocidium multicaule)
Medicinal Exotic Perennials: *Turtlehead: (Chelone glabra), *Sage (Salvia spp.) *Meadow Sage (Salvia pratensis), *Oregano, *Thyme, *Dragonhead (Dracocephalum spp.), *Lavender (Lavandula spp.)
Exotic Perennials: Catmint (Nepeta cultivars) N. cataria can be invasive. Very important long-blooming plant for honeybees and bumblebees
California poppies (Eschscholzia californica) can be weedy, Liatris spp., Comfrey (Symphytum spp.), Red Clover (Trifolium pratense), Cardoon (Cynara cardunculus) comes with an invasive warning, Hollyhocks (and other Malva spp.), Wine Cup (Callirhoe involucrata), Russian Sage (Perovskia atriplicifolia), Sea Holly (Eryngeum spp.), Globe Thistle (Echinops ritro), Caterpillar Flower (Phacelia bolerandi) works in dappled shade, Masterwort (Astrantia major), Sneezeweed (Helenium autumnale), Verbena spp.,
Exotic Annuals: Borage (Borago officinalis) NB for nectar, Hairy Vetch (Vicia villosa) can be weedy, Moroccan Toadflax (Linaria maroccana) plant instead of invasive toadflax spp., Blue Shrimp Plant (Cerinthe major), Globe Gilia (Gilia capitata), Zinnias (choose the large ones) Calendula (Calendula officinalis) long-blooming and open access,
Edible Exotic Annuals: Scarlet Runner Beans, squash (Cucurbitae)
Medicinal Exotic Annuals: *Buckwheat (Fagopyrum esculentum), *Tobacco (Nicotiana rustica),
*Nightshades (Tomato, Pepper, Eggplant, Potato),
Exotic Tubers: Dahlias (Avoid doubles)

Extra Edibles: Let some of your veggies bloom for bees: radishes, kale, leeks, carrots, parsnips
Extra bee-friendly herbage: cilantro, fennel and dill
Warning: Don’t plant Sainfoin (Onobrychis spp.)—I have recently found out that it is invasive in certain areas.

Sources and Recommended Reading:
Victory Gardens for Bees: A DIY Guide to Saving the Bees by Lori Weidenhammer
Gardens Aflame: Garry Oak Meadows of BC’s South Coast by Maleea Acker, published by New Star Books
Common Pollinators of British Columbia: A Visual Identification Guide created by Border Free Bees and the Environmental Youth Alliance (available as a pdf online).
Bees: An Identification and Native Plant Foraging Guide by Heather Holm. (Best for Eastern US, but some good info on more widespread native plants for bees.)
The Bees in Your Backyard: A Guide to North America’s Bees by Joseph S. Wilson and Olivia J. Messinger Carril.
Conserving Bumble Bees: Guidelines for Creating and Managing Habitat for America’s Declining Pollinators by the Xerces Society for Invertebrate Conservation. (This is available online for free.)
Bumblebees of the Western United States by Koch, Strange, and Williams
Bumblebees of North America: An Identification Guide by Williams, Thorp, Richardson and Colla, Princeton University Press, 2014.


Information on how to avoid neonicatinoids:
http://northcoastgardening.com/2015/02/nurseries-neonicotinoid/


Tuesday, March 21, 2017

Newsy Mcnews Face




I have news!!!!! First off, I am heading to Vancouver island to do a talk on gardening for bumblebees for the Russell Nursery Anniversary talks series this Sunday at 1:30 pm tickets are $18. The talk is at Kildara Farms, located in Deep cove, at the tip of the Saanich peninsula. I’m so looking forward to having the space and time to rattle on about bees for an hour and a half—much more time than the 10-minute Ted Talk model. This lecture will stuffed with all sorts of ideas for bumblebee gardens and I’ll have time to go into more detail with some of my adventure stories.


If you are in Vancouver, please head to the Environmental Youth Alliance Wild About Spring Celebration—you must register to participate, but you can go to a wild pollinator workshop and take home some native plants. Saturday, March 25, 12:30 pm Strathcona community garden.

I’ve just returned from Alberta (see the posts below) where I’ve been to Seedy Saturday in Calgary, and Seedy Sunday in Edmonton. I met all sorts of gardeners who are interesting in growing flowers and building nesting boxes for over 20 species of bumblebees they have in that province. Check out the links on my web site to another site called Border Free Bees with a file on how you can build a nesting box for bumblebees in a info sheet compiled by bumblebee scientist Ralph Cartar and Luc Pelletier.

I also had a really interesting conversation with a veternarian who told me that her profession is increasingly being asked to diagnose and treat managed bee species. Stay tuned for more thoughts on that topic.

Photo: A Bembix sand wasp, which is the carnivore that evolved into the vegan and became the first bee. These are not the wasps that "bring the sting". They are sweet, gentle, and quite beautiful.

I am thrilled to be honored with the nomination for an INDIE book of the year award. This has just been announced and it’s great timing as we try to get copies of Victory Gardens for bees into peoples hands as they hit prime gardening season. Again, I’d like to acknowledge the team—team BEE—especially my editor Carol Pope who worked to make this book work for bees. Someone in Calgary mentioned that they wanted to buy the book as a coffee table book—which is great—but I want you to use it, make it dog-eared, write notes in the margins—put that book to work gardening for bees. You could always buy two copies—one for the garden and one for the coffee table which is what I know at least one person has done!!!!!

And on that note: put a couple of dates on your calendar: Alpine Garden Club of BC plant sale at VanDusen gardens, April 1, VanDusen Botanical Garden plant sale April 30. Check the plant shop at UBC Botanical Gardens and Figaro’s Garden—they will set you up with pesticide free bee plants.


Also, I really encourage everyone to try growing at least one plant from seed this year. There is nothing more inspiring, than the miracle of seed-to-flower-to fruit. Start with chives or nodding onions, and prepare to get hooked on a new healthy habit. I'm so happy that West Coast Seeds is now carrying my book!!!!!!!!!! So order your copy and put in your seed order at the same time!

 Photo: Did you know blueberries need bumblebees for polliantion? Join me in a picnic with the bumblebees at UBC Farm.


 First Saturday Tea with the Bees:
 The first Saturday in May and June we'll be hosting tea with the bees in the blueberry rows and orchards. Let's start a family tradition of seasonal picnics celebrating the connection between what's bloomin' and what's pollinatin'.



Life in the Bee Lane:
I have attended one public consultation meeting for The Arbutus Greenway plan, and I’m happy to announce the City of Vancouver is planting a temporary bee lane along the path with pollinator wildflowers. Please go online and fill out the survey and encourage the planners to make the bee lane a permanent feature. As we lose backyard bee habitat every day to developers and people add honeybees to the urban environment, we need to keep adding bee forage to keep up and feed our precious native wild bees.


Neonics in the News:
The Canadian government is getting serious about banning neonics. (Or is it one neonic, singular?) Anyhow, please tell the government to ban Imidacloprid—either via the Wilderness Committee links or the David SuzukiFoundation or both-- BEFORE March 23. Do it today!!!!!

Photo: Did you know that Yellow Cosmos (Cosmos sulphureas) is a dye plant!!!! Can’t wait to grow some this year). The photo above was taken at City Farmer in Vancouver.

All the photos except the final one were taken at Earthwise  Farm and Garden in Delta. This is one of the best places to buy organic flowers for bees in the Lower Mainland.

Best of luck with all your gardening adventures!!!

Cheers,
Lori





Monday, March 20, 2017

Postcards from Edmonton Seedy Sunday


The lovely folks from The Garlic Garden, based in Yorkton, Saskatchewan.


The Garlic Gardens' crop cover cocktail for the health of bees, birds, butterflies, and the soil.


I sat next to the honeybee people trying to woo folks over to Team Bumblebee!!!!


The Edmonton Native Plant Group had an awesome display.




Good Note Community Farm had natural weaving activities for the kids. No goat kids though. No goat yoga. Next time.




I love the aesthetics of the vounteers' name tags.


The gentleman from Sherwood's Forests Tree Farm teaches me about hardy fruit trees. Apparently chokecherry cultivars are better than natives in the city because they don't carry the diseases that the native ones can spread.

Thanks again to everyone for the great conversations, the book sales, your enthusiasm, and those green onion cakes!!!!!!

I Heart Seedy Saturdays and Sundays!!!!


 Thanks again to the organizers of Seedy Saturday in Calgary and Seedy Sunday in Edmonton. These grass-roots events are essential for community engagement through gardening. The volunteerism that makes these events happen is priceless. The milkweed seeds above are from Wild About Flowers based in Okotoks. Arden is about to add some new information on the relationships of bees to the flowers she sells. I'm excited!!!!!



I think these are about the most gorgeous pussy willows I've ever seen from Bretin's Flower Farm.


Maddy from Custom Woolen Mills was creating a buzz around her natural dye kits.




For the peeps that live in Calgary, please try to attend Lyndon's talk. So nice to see this poster at the venue for Calgary Seedy Saturday. I love the cross-pollination of spring garden talks as we all get ready to support our pollinators as a community.


Check out these amazing chinook clouds I saw from the bus window enroute from Calgary to Edmonton!

Saturday, March 18, 2017

How You Can Help Alberta's Beautiful Bumblebees


Bumblebee Species of Alberta:  21 species plus 4 cuckoo bumblebee spp.

Hey Alberta, you have an abundance of bumblebee species to celebrate! These are the bees that give you big fat tomatoes, eggplants, peppers, squash, blueberries and pollinate many beautiful native and cultivated flowers and berries. I've listed the species below so you can research any one or more in detail and I've added some tips on how you can help these sweet and vulnerable species.


1) White-shouldered Bumblebee (Bombus appositus) long-tongued
2) High Country Bumblebee (Bombus kirbiellus , formerly B. balteatus) long-tongued, rare
3) Black-notched Bumblebee (Bombus bifarius) medium-tongued
4) Cryptic Bumblebee  (Bombus cryptarum) (formerly B. moderatus) medium-tongued
5) Great Basin Bumblebee aka Central BB (Bombus centralis) long-tongued
6) California Bumblebee (Bombus californicus aka B. fervidus ssp. Californicus) and Golden Northern Bumblebee (Bombus fervidus) long-tongued
7) Yellow-fronted Bumblebee (Bombus flavifrons) medium-tongued
8) Frigid Bumblebee (Bombus frigidus) rare, medium-tongued
9) Brown-belted Bumblebee (Bombus griseocollis) medium-tongued
10) Hunt’s Bumblebee (Bombus huntii) medium-tongued
11) White Tail Bumblebee (Bombus jonellus) medium-tongued, Northern
12) Black-tailed Bumblebee aka Orange-rumped Bumblebee (Bombus melanopygus) medium-tongued
13) Mixed Bumblebee aka Fuzzy-horned Bumblebee (Bombus mixtus) medium-tongued
14) Nevada Bumblebee (Bombus nevadensis) long-tongued
15) Western Bumblebee (Bombus occidentalis) short tongued, rare
16) Perplexing Bumblebee (Bombus perplexus) short-tongued, rare
17) Red-belted Bumblebee (Bombus rufocinctus) short-tongued
18) Forest Bumblebee (Bombus sylvicola) uncommon, medium-tongued
19) Tri-coloured Bumblebee (Bombus ternarius) medium-tongued rare in west, more common in east
20) Yellow-banded Bumblebee (Bombus terricola) short-tongued, rare
21) Half-black Bumblebee (Bombus vagans) medium long-tongued
Cuckoo:
1) Ashton Cuckoo Bumblebee (Bombus bohemicus)
2) Fernald Cuckoo Bumblebee (Bombus flavidus, formerly B. fernaldae)
3) Indiscriminate Cuckoo Bumblebee (Bombus insularis) long-tongued
4) Suckley Cuckoo Bumblebee (Bombus suckleyi) uncommon (ICUN red list)

Sources: 
 Special thanks to Lincoln R. Best for help compiling the list above.


What Makes a Good Bumblebee Garden?
•A biodiverse selection of organic bumblebee flowers that bloom in each season (Spring, Summer, Fall) with no forage gaps: for an Alberta Bumblebee plant list see the post below.
Flowers with a variety of corolla lengths to suit small, medium and long-tongued bumblebee species
•Local organic native bumblebee plants that are high quality source of nectar and pollen
•Nesting and hibernation sites
•The inclusion of plants that exclude other bee species to ameliorate competition, esp. plants that exclude honeybees, including buzz-pollinated flowers
•Long-blooming drought tolerant plants
•Medicinal plants for bumblebees to help them fight diseases and pests
•Interconnected hotspots of forage: use hedgerow model, ditches, boulevards to provide corridors for bumblebees to date, mate and procreate
•A critical mass of interconnected forage with groupings at least 1 m square, herbaceaous plants, shrubs and trees with high blossom and high reward density (esp. in areas with a high honeybee population
•Areas with forage spots that are protected from wind
Steps you can take to protect bumblebees:
Do not load your neighborhood with honeybees that compete directly with native bees
Do not support greenhouses that use farmed bumblebees, which have been advocated in the spread of disease and steep decline in native bumblebee species.
If you see a stranded bumblebee, give her some sugar water (50/50) or just water and put her safely in the sun near some flowers.
Educate other people about the importance of bumblebees.
•Take part in the citizen scientist studies of bees such as The Great Canadian Bumblebee Count. Record your sightings. Take photos of the bee from as many angles as possible: Think head, thorax, abdomen—get all the parts documented.
Build a bumblebee box for families of bees to move into your garden!: Advice for deploying bumble bee nest boxes (domiciles), January 2016, Luc Pelletier & Ralph Cartar*
 Local native plants and seeds: http://www.wildaboutflowers.ca/
Native Plants for the Short Season Yard by Lyndon Penner. (This is a must-have book for the Albertan bumblebee gardener!!!!)
My book is now available through West Coast Seeds! Add a copy to your seed order! Victory Gardens for Bees: A DIY Guide to Saving the Bees

Resources for Alberta Bumblebee Gardeners


Bumblebee Plants for Alberta 
This list is a work of progress: check back for updates as I re-organize it to make this easier to read.
* Denotes a medicinal plant for bees
BOLD denotes special interest for bumblebee plants (buzz pollinated, longer corollas or special relationships, ie trip pollination)
Native and Near Native Shrubs:
Salmonberry (Rubus spectabilis), Oregon Grape (Berberis spp.), Willow (Salix spp.), Sumac (Rhus spp.), Red Osier Dogwood (Cornus stolonifera), Blue Elderberry (Sambucus cerulea), Wax Currant (Ribes cereum), Clove Currant and other ribes spp., Wild Raspberry, Kinnikinnik (Arctostaphylos uva-ursi), Blueberries (Vaccinium spp.), High Bush Cranberry (Viburnum trilobum), Wood’s Rose (Rosa Woodsii), Prickly Rose (R. acicularis), Blueberry—low bush vaccinium myrtilloides and cultivars, Potentilla spp., Labrador tea (Rhododendron groenlandicum), Snowberry (Symphoricarpos albus)
June Gap: Ninebark (Physocarpus spp.), Spirea spp., Mock Orange (Philadelphus lewisii), hardy roses
Later Shrubs: Buck Brush (Symphoricarpos occidentalis), Rabbit Brush (Chrysothamnus naseosus)
Native Trees Chokecherry, Crabapple, Pincherry, Saskatoon (and many other native fruit trees), Western Mountain Ash (Sorbus scopulina)
Native Vines: Purple Clematis (Clematis occidentalis) Virgin’s Bower Clematis (Clematis ligustifolium) beware of invasive look-alikes
Exotic Trees: Hawthorn (Crataegus spp.), Linden (Tilia spp.) avoid silver linden (Tilia tomentosa); Stone Fruit Trees: apple, cherry, peach, apricot, pear, quince, plum; Redbuds (Cercis spp.);
Exotic Shrubs: Spirea spp., Climbing roses
Native and Near Native Perennials: Native violets, Prairie Crocus (Pulsatilla patens), Bleeding heart (Dicentra spp.), Solomon’s Seal (Polygonatum spp.) Heartleaf Golden Alexanders (Zizea aptera)
 Nodding onion (Allium cernuum) and other native alliums, Canadian Columbine (Aquilegia canadensis) and other Aquilegia spp., Arrowleaf Balsamroot (Balsamorhiza sagittata), Prairie Smoke (Geum trifolium), Few-Flowered Shooting Star (Dodecatheon pulchellum)
Milk Vetch (Astragalus spp.) toxic, Locoweed (Oxytropis spp.) toxic, Native Silvery Lupin (Lupinus argenteus) and other Lupinus spp. toxic, Blue-eyed Mary (Collinsia spp.), Broomrape (Orobanche spp.)
Yarrow (Achillea Millefolium), Yellow Rattle (Rhinanthus minor), Potentilla spp. native species and cultivars are great
Common Harebell (Campanula rotundifolia and other native and exotic spp.), Native Larkspurs Delphium bicolour, D. glaucum or Nuttall’s Larkspur (D. nuttallianum) HIGH toxicity warning, Rocky Mountain Bee Plant (Cleome serrulata), Anise Hyssop (Agastache foeniculum)
Penstemon spp., Canadian Milk Vetch (Astragalus Canadensis and other native spp.), Scarlet Globe Mallow  (Sphaeralcea coccinea) (red-listed grassland species), Plains Prickly Pear (Opuntia polyacantha), Gumweed (Grindelia spp.)
Erigeron spp., Lilies (Erythronium spp.), Blue Gentian (Gentiana spp.), Jacob’s Ladder (Polemonium spp.), Cranesbill Geranium (Geranium spp.)
Monkey Flower (Mimulus sp.), Summer Paintbrush (Castilleja spp.)
Native Annual: Bienenfreunde aka Lacy Phacelia (Phacelia tanacetifolia)
Late-Blooming Native Asteraceae: Joe Pye Weed (Eutrochium maculatum) Blanket Flower (Gaillardia spp.), Tickseed (Coreopsis spp.), Pearly Everlasting (Anaphalis margaritaceae), Asters (Symphyotrichum spp.), Goldenrod (Solidago spp.), Coneflowers (Echinacea spp.), Coneflowers (Ratibida spp.), Black-eyed Susan the Alberta native is Rudbeckia serotina
Exotic Perennials: *Turtlehead: (Chelone glabra), Catmint (Nepeta cultivars) N. cataria can be invasive, *Sage (Salvia spp.) *Meadow Sage (Salvia pratensis), *Oregano, *Thyme, *Dragonhead (Dracocephalum spp.), California poppies (Eschscholzia californica), Verbena spp.
Lavender (Lavandula spp.), Liatris spp., Comfrey (Symphytum spp.), Red Clover (Trifolium pratense), Hollyhocks (and other malva spp.), Wine Cup (Callirhoe involucrata), Russian Sage (Perovskia atriplicifolia), Sea Holly (Eringeum spp.), Globe Thistle (Echinops ritro), Cardoon (Cynara cardunculus) comes with an invasive warning, Caterpillar Flower (Phacelia bolerandi), Masterwort (Astrantia major), Sneezeweed (Helenium autumnale)
Exotic Annuals: Borage (Borago officinalis), *Buckwheat (Fagopyrum esculentum), *Tobacco (Nicotiana rustica), Calendula (Calendula officinalis), Hairy Vetch (Vicia villosa) weedy warning, Blue Shrimp Plant (Cerinthe major), Moroccan Toadflax (Linaria maroccana)
Scarlet Runner Beans, *Nightshades (Tomato, Pepper, Eggplant, Potato), squash (Cucurbitae)
Globe Gilia (Gilia capitata), Zinnias (choose the large ones), Dahlias (Avoid doubles)

Let some of your veggies bloom for bees: radishes, kale, leeks, carrots, parsnips
Extra bee-friendly herbage: cilantro, fennel, dill, rosemary, mints, winter and summer savoury

Warning: Don’t plant Sainfoin (Onobrychis spp.)—I have recently found out that it is invasive in Alberta.
Sources and Recommended Reading:
Local native plants and seeds: http://www.wildaboutflowers.ca/
Native Plants for the Short Season Yard by Lyndon Penner. (This is a must-have book for the Albertan bumblebee gardener!!!!)
Bees: An Identification and Native Plant Foraging Guide by Heather Holm. (Best for Eastern US, but some good info on more widespread native plants for bees.)
(You can buy these on Amazon, or support your local bookstore!)