Trees for Bees

• By John Bornsworth
• June 25, 2020

“If the bee disappeared off the face of the Earth, man would only have four years left to live.” – Albert Einstein

 

There is merit to this bold statement. Bees, butterflies, bats and other creatures pollinate the fruits, vegetables, nuts, and other plants we eat. Honey Bee, insect genus Apis, are our most important pollinators for edible flowers, fruits, and vegetables. Without bees to pollinate our plants, our sources of food would quickly decline. Our supermarkets and dining room tables would look dramatically different without our pollinators. Not to mention the important role bees play in native plant propagation. Without our local bee’s and bats, many native plants would fail to propagate, resulting in ecosystem and habitat loss. Needless to say, without bees, we’d be in a lot of trouble. These days bees are facing a lot of challenges. Insecticides fungus, mites, and even natural disasters, have greatly reduced bee populations around the world. So what can we do to help the bees?

When you ask a gardener what you can do to help bees, they might suggest you plant a pollinator garden. When people think of planting pollinator gardens, plants such as daisies, zinnias, asters and salvia, oregano, mint and lavender, tend to come to mind. But if you really want to provide bees with the maximum amount of protein rich food, consider planting trees! A single tree can produce many times the amount of pollen an entire complex pollinator garden provides.

Reasons why trees provide substantial habitat improvement over garden flowers include:

• Physical size and dimensions. Trees are three dimensional, they grow into the air and produce thousands of more blossoms than garden flowers or shrubs.
• Protein content. Protein content of some tree pollen is much higher than garden flowers – sort of like a bee and pollinator superfood.
• Travel time between flowers. Bees want flowers in close proximity, less than 6 inches away normally. On tree flowers, this is easily doable, but garden flowers are often much further than 6 inches apart – even more so with sporadic herbaceous flowers in a lawn.

Trees specifically adapt to assist pollinators in their journey:

FRUIT TREES, INCLUDING FRUITLESS VARIETIES
Fruit trees like apples, crabapples, plums, pears, and peaches, are all excellent sources of protein rich pollen and nectar for bees. Many of these varieties require bees to pollinate them before they make fruit. If you don’t want fruit growing in your yard, consider a fruitless variety. Most fruit trees produce flowers in the spring.

BIG LEAF MAPLE, Acer macrophyllum
Big Leaf Maples are one of the first trees to establish in new forests. This species if also one of the main sources of pollen for mason bees. It provides forage for some animal species, and act’s as a nurse tree while other plant species develop under it’s canopy. This is a low-land forest tree. Native from, Southern Alaska, all the way to CA. This tree produces a great amount of pollen. It is pollinated by many species, including multiple types of bees, beetle, and fly.

LINDEN TREES, Tilia cordata & Tilia americana
The Linden tree produces small yellowish-white flowers which are also very fragrant. The blooms arrive beginning in late spring and continue into summer. Consider both the Silver Linden, and the Littleleaf Linden tree.

BLACK LOCUST, Robinia pseudoacacia
In late spring, this locust will produce clusters of aromatic white flowers. A beautiful yellow color appears in the fall. Please note, this species is not suitable in a garden, because it drops a lot of seed, and propagates which creates a lot of maintenance. It also has brittle wood. A better place for this species is in an out-of-the-way area. Consider using it as a hedge row.

SOURWOOD, Oxydendrum arboreum
A native to the east, this tree is cherished for its stunning long white clusters of perfumed flowers which arrive in spring, and are then replaced by interesting seed capsules, which will hang on the tree into some time in winter. To make it even more of a spectacle, the leaves of this tree turn into blazing shades of orange, and then change to scarlet red, and then purple in fall.

BLACK TUPELO, Nyssa sylvatica
This tree is native to eastern states. It is commonly planted as a shade tree. Prized for it outstanding fall color, the flowers are not particularly fancy, however they make excellent honey.

LIQUIDAMBAR, Liquidambar sp.
One of the more well known varieties is the American Sweetgum. They are tall, upright trees, and create beautiful colors in the fall. The flowers, although unremarkable, still attract bees.

CRAPEMYRTLE, Lagerstroemia sp.
This tree is cherished for its very colorful flowers which arrive from late spring through summer. These trees are available in a variety of colors; white, pink, red, and purple. The leaves will turn bright yellow, orange, or red in fall. The bark peels back exposing the smooth, cinnamon-brown trunk.

KOELREUTERIA, Koelreuteria sp.
Many people value the tree for it’s interesting Japanese lantern-like seed capsules, which will hang through fall. First, large clusters of yellow flowers emerge in summer. The divided leaves will turn yellow in fall. One variety of Koelreuteria is the goldenraintree.

INDIAN PLUM, Oemleria cerasiformis
The Indian Plum is unique in that it is one of the first to flower, often in later winter, which makes it a valuable food source for pollinators who emerge early in the season. This species will grow in many different types of soil. It will grow in both full sun, or partial shade.  You can prune the Indian Plum into a shrub, but or allow it to grow into a small tree. This species can be found from British Columbia, Canada, all the way to the Willamette Valley of in Oregon state.

SERVICE BERRY, Amelanchier alnifolia
This tree is best known for it’s edible berries which Native American tribes used for food forage. It is often used in habitat restoration project because it helps prevent erosion, and provides food for all kinds of animals including mammals, birds, and insects. This is adaptable and will grow in a large variety of conditions. It is commonly found growing in Washington state, and all across the PNW.

OREGON GRAPE, Mahonia aquilifolium/nervosa
The Oregon Grape produces bright yellow flowers in later winter, making it a valuable source of nectar for bumblebees and mason bees as they emerge early in the season. Oregon Grape is tolerant, and will grow in a large variety of conditions, and does well when planted in lowland areas. It is often used as a shrub in native landscape design projects.

BITTER CHERRY, Prunus emarginata
Another excellent species in habitat restoration projects is the Bitter Cherry which helps to prevent erosion, while also producing food for many forms of wildlife. This plant can be grown as a shrub, or small tree. Flowering in April and May means it will provide pollen for spring pollinators, especially the spring-flying mason bee.

PACIFIC NINEBARK, Physocarpus capitatus
Another big producer of food for both mammals and insects, the Pacifit Ninebark provides large amounts of pollen for hungry insects, from it’s small clusters of white flowers. If your planting space is in partial shade, this species will live happily there. A rather short plant, it’s really more of a shrub than a tree at just 4-5 feet tall.

RED ELDERBERRY, Sambucus racemosa
Another small tree, which blooms early, the Red Elderberry blooms large clusters of small white flowers. These serve as an important source bees as well as hummingbirds. In the summer, the flowers transform into big clusters of small red berries which are cherished as medicine for its anti-viral and immune boosting properties. You can grow Red Elderberry in containers, or in the ground, wherever it can enjoy full sun or partial shade.

Here are some more tips, on how to help bees:

1. Don’t use insecticides – Insecticides kill all insects. Systemic types (e.g., neonicotinoids, including imidacloprid) have proven to harm honey bees. These chemicals are so harmful to honey bees, that they have ben banned from use many countries.
2. Choose plants which feed pollinators – We want to encourage you to choose native plants, which provide large amounts of nectar and pollen. Choose plants which produce a variety of colored flowers. Bees find blue, violet, white and yellow flowers most attractive, so try and work all of these colors into your landscape. Also choose plants that flower at different times in the season so there is a constant source of food for them in your garden. Bees need to eat everyday when they are active, so you’ll want a garden which produces flowers from later winter through fall.
3. Provide a source of water for pollinators – A tiny bit of water in your landscape, is all they need to help them stay hydrated. Honey bees actually use water to cool their hive, and to dilute honey when feeding baby bees.
4. Spread the word – Encourage your friends, neighbors, and garden buddies to plant trees, shrubs, and other plants which attract and produce lots of food for bees and other pollinator species. Also be sure to discuss how pesticides harm bees, to avoid the use of these chemicals, and to never use them when bees are active in your garden.

Next spring, rather than not mowing the dandelions in your lawn to satisfy bee cravings: plant a tree! This will assist bee populations far more than garden and lawn flowers will.

 

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