Showing posts with label willow. Show all posts
Showing posts with label willow. Show all posts

Bumblebees Part 1: Bumblebee Lives

Note to readers: For the first installment of this series on bumblebees, see "The Funny Fuzzy Bumblebee."


BUMBLEBEE QUEENS EMERGE in early spring, sometimes as early as February, from holes in the ground called hibernacula. They then start looking for food. A good food source for queen bumblebees in early spring is the pollen from willows (Salix spp.). However, if there are nectar-producing plants in bloom, they will visit these too.


Before she can start to raise a family, each queen must find a place to build a nest. If you notice a large bumblebee flying back and forth over your garden in early spring, this may well be a queen intent on finding a location suitable for raising her young.

Bumblebee nests offer us a charming example of nature’s unwillingness to let anything go to waste. The bees prefer to nest in a dark, sheltered cavity filled with soft insulating material. However, although they can rearrange materials within their nests, they don’t bring insulating materials into the nest themselves. So nature, the ultimate recycler, allows queen bumblebees to inherit the perfect nesting spots, no longer needed by the original owners. That is, abandoned mouse nests.

Brian L. Griffin, author of a wonderful little book called Humblebee Bumblebee: The Life Story of the Friendly Bumblebees and Their Use by the Backyard Gardener, tells us that once she’s found a suitable spot, the queen bumblebee builds her nest, inserting her eggs into small wax containers. Henceforth, when not looking for food, she will actually “brood” the soon-to-be bees by lying on the egg cluster and warming it with her body.

After about a week, the larvae turn into pupae, becoming adults after a total of about 25 days. Once the first crop of worker bees emerges, the queen ceases leaving the nest, letting the workers take over the job of finding food. The colony grows larger as more workers are produced, each generation bringing more food to feed more baby bees. (According to Griffin, later generations of worker bees are actually larger than the first group raised by the queen alone, because the later bees get more food than the early bees do.) Eventually a bumblebee colony can become quite large, beginning to resemble “a medieval castle with turrets and domes ever rising,” Griffin says.

But this magnificent colony lasts only until the end of summer. In August or thereabouts, the queen, who formerly laid only eggs of female worker bees, begins to lay male eggs and large queen eggs. When the males and queens reach adulthood, they leave the colony, meet, and mate. Each queen eats heartily to build up a supply of fat, digs a hibernaculum, and tucks herself away for the winter months.

This series of posts on bumblebees is taken from an article I originally wrote for Northwest Garden News.

A Walk on the Shady Side






LET'S TAKE A STROLL down a garden path. These photos show two views of a Pacific Northwest woodland garden designed to attract songbirds and other wildlife. When I took the bottom photo, I was standing right in front of the living room windows of my house. The top photo shows a view of the same garden looking toward the house.


I designed this particular spot as what I like to call a songbird sanctuary--a serene, shady spot that will attract birds. This is a good garden style for a location just outside the windows of a house: It creates a pretty view, attracts birds to location where you can easily enjoy watching them, and creates privacy. It works well even on the north side of a house (where it's just too shady for many plants) because woodland plants are naturally shade-tolerant.


Note that this garden offers plants at every level: groundcovers, taller perennials, shrubs, trees. It also includes both deciduous plants and evergreens. This gives birds the shelter they need in order to hide from predators, shelter from bad weather, and find suitable spots for nests. Different birds have different needs, so if you want to attract a variety of species, a varied environment such as this one is important.


Although you can't see this, it's also important to note that no pesticides were ever used in this garden. Almost all species of birds are dependent on insects to feed their young. Many species, such as wrens, eat only insects: They will not visit your garden unless they can find insects there.


Let's take a closer look at the bottom photo: The focal point of the photo is a small "tree" that really isn't a tree at all. It's a dwarf willow, which I pruned to look as much as possible like a small native tree called a vine maple (Acer circinatum). Why not just plant a vine maple? Because it would take too long to grow. I did plant vine maples in other spots in the garden. In fact, though you can't see it, there's one in the background of this photo. There are also a few mature trees in the garden; fortunately for me, they came with the house.


But sometimes a gardener just needs some instant gratification, and willows -- which grow fast -- are good little instant gratifiers. (They also attract butterflies and other pollinators, btw.) Yet there was a price to be paid for my lack of patience: A willow wants to have a lot of stems; I had to keep pruning it in order to keep it down to just two. This required a fair amount of maintenance.


At the foot of the willow is a small pond. Birds like and need water, so it's important to include at least a small water feature if you're creating a spot for them. You can see the spiky foliage of a slough sedge (Carex obnupta), a large wetland native, right at the bottom of the willow: That sedge is growing directly in the water.


In front of the pond is a planting of native bleeding heart (Dicentra formosa) and redwood sorrel (Oxalis oregona). These tough little groundcovers love moisture and shade and cover bare ground rapidly, which really helps to keep weeds out. The larger plant on the left, with pink flowers, is a common garden bleeding heart (Dicentra spectabilis). Though it's not native, it's an attractive, hardy, shade-tolerant plant that hummingbirds visit in early spring.


In the top photo, you can see that the pond is located right in front of one of the downspouts from my house. This isn't an accident. If you have a wet spot in your garden, use it! Bad drainage? As long as you can direct the water away from your house, this is one of those take-lemons-and-make-lemonade situations. Birds and other wildlife love these little spots where moisture collects, and so do many plants.


Going back to the bottom photo: Behind the willow, on the other side of a path, is a native serviceberry (Amelanchier alnifolia). This is another fast-grower that helps to create the illusion of a woodland garden complete with trees, even though technically it's more of a large shrub. An advantage for a bird garden is that, as the name implies, serviceberry produces edible berries, which both humans and many birds enjoy. If you're planting a spot for birds, you'll certainly want to include some native shrubs that produce berries for birds; in addition, a bird feeder is also useful if you want to attract seed-eating birds such as chickadees.


The serviceberry is covered in beautiful white flowers in the spring. And as you can see, the bleeding hearts also bloom reliably, even in shade. However, it's hard to get a lot of bloom in a woodland garden. There just isn't enough sun. To really appreciate a woodland garden, you need to be able to enjoy foliage colors, textures, and shapes, and the shifting patterns made by whatever sunlight penetrates your canopy of leaves.


The top photo shows the "sunny" side of this garden. Even though this area gets more sun than the spot right next to the house, those irises you can see in the bottom left-hand corner never did bloom. I enjoy the way their sword-like foliage contrasts with the soft groundcovers that surround them and with the froth of forget-me-nots that used to volunteer in the garden every year. But that's the sort of subtlety you have to be able to appreciate if you want to get full enjoyment from your woodland garden. If your idea of a beautiful garden features dahlias the size of dinner plates, this is not the garden for you!


Over on the left of that top photo, you can see a few pinkish-purple rhododendron flowers; the rhodie was dying a slow, lingering death over on the other side of the house when we bought the place. I moved it here, then planted a native rhodondendron (R. macrophyllum) right next to it. If I had kept the house, I probably would have gotten rid of the non-native rhododendron once the native one was big enough. However, when I sold the house the native was several years old and still only about 6 inches tall. So the non-native rhodie will be serving as a "placeholder" for a long time to come.


This illustrates another important point about woodland gardens: They take take time. You can push a shade garden along by using tricks such as I've mentioned here (prune a shrub to look like a tree, take advantage of fast-growing or already established plants while you wait for the plants you really want). But when all is said and done, a woodland garden takes time because woodland plants take time: Trees, even large shrubs, just don't happen over night. The garden you're looking at in these photos was probably about 8 years old when these pictures were taken, and it's still far from mature. One day, if the vine maple, the Pacific rhododendron, and other native plants are left to grow, this garden will be far more beautiful than it is now.