Wednesday, January 11, 2017

Do it Yourself: Homes for Solitary Bees

Image from www.xerces.org
Many species of bees will make use of nesting structures such as Bee Nest Boxes.
A Bee Nest Box is similar to a bird house, except it is designed for native species of bees, which are some of our key pollinators.

Almost 1/3 of native bees nest in hollow stemmed plants. The female will build a "room" for an egg, complete with pollen and nectar. She seals off the "room" and then starts another one, continuing until the end of the stem. When the eggs hatch they will eat the pollen supply and then overwinter in their "room," emerging from the stem the next spring.
Many of Ontario's native bees are ground nesters and need un-mulched or bare patches of the garden. Leaving a pile of sticks in the back of the garden, not 'cleaning' the garden in the fall is beneficial for nesting and overwintering pollinators which depend on standing, dead stalks (ex. raspberry) to survive the winter.

Remember, the bee nests provide habitat, but it is also important to have food nearby. Planting native plants that flower from spring to fall will provide food for the bees and other pollinators, and will also make an attractive and low maintenance garden.

Pollinators such as bees can thrive in urban environments, particularly when we incorporate their habitat needs into our gardens. This can be as simple as adding native wildflowers to the garden, or can involve creating pollinator habitats in city parks. Not using chemicals such as herbicides and pesticides is also important.

Pollinators need a variety of flowering plants throughout the spring, summer and fall, nesting sites and a water source. Visit the Pollinator Plant page to learn more about native pollinator-friendly plants.

Bees and other pollinators cannot use a conventional bird bath. Instead, line a shallow pan with rocks or marbles and regularly add fresh water.

By creating nesting habitat, and planting native wildflowers, Hamilton will be creating a paradise for pollinators!

BUILDING A BEE NEST BOX

Pollination Guelph has a great design (which we use, see below). Check out their Making homes for Pollinators resource page.
Also www.xerces.org has some great designs for all types of bee nests.

What you will need:
5 pieces of wood about 1” thick


left top: 6x8”

 right top: 5x8”

 left bottom: 4x7”

 right bottom: 3x7”

 back: 5x5”

Also:
  • 12 galvanized nails
  • 1-2 medium screw eyes
  • Hammer
  • Sandpaper
  • Drill (if desired)
  • Non-toxic paint, stains (if desired)
  • String (to hang/attach nest)
  • Post/Stake (if desired)
Directions for the box:

1. Nail the left top piece onto the top edge of the right top piece using two nails.
2. Nail the left bottom piece onto the edge of the left top piece using two nails.
3. Nail the back piece onto the top pieces using four nails. It can be nailed flush with the
inside edges (as shown in the photo), or along the outside edges.
4. Nail the bottom pieces onto the other pieces using 4 nails, to form a square or diamond.
5. Use the sandpaper to smooth any rough edges.
6. Screw the eye hook into the top of the box, about 1/3 of the way from the back. A second hook
can be used at the front to prevent the box from swinging in the wind. Pre-drill the hole if needed.
7. If desired, the outside of the box can be painted or stained in any design you choose.

Directions for the nesting tubes:
Any type of dead stems with a hollow or pithy stem can be used for nesting tubes. Example species include goldenrod, Queen Anne’s Lace, sumac, teasel, cattails/reeds, elderberry, parsnip, rose, and raspberry.

Different sized twigs are recommended as different bees prefer stems of different diameters and lengths. One end of the twigs should be closed (e.g. by a knot or stem node) so that the tube has only one opening; the female bee will plug the front entrance with mud after she finishes nesting.

Pack the tubes in the box tightly so that the tubes remain horizontal and will not fall out if
moved. Tubes should end just before the edge of the box overhang, to protect the bees from the elements.

Placement and Maintenance:

The completed nest can be placed on a building, post, or in a tree. The nest should be kept level, with the entrance facing east or south-east. Direct sunshine in the morning helps warm the bees up in preparation of flight. Ensure that the nest is stable and not going to move in the wind, or else the bees will nest elsewhere. The actual height doesn’t matter, although 2 to 6’ (0.6-1.8m) from the ground is good.

It is best to put out nests in early spring, although it is never too late to put a new one out, as females
of some species will lay eggs throughout the year. If a female finds a tube suitable, she will lay a
series of eggs on a pollen and nectar ball, separated by partitions. As the eggs hatch, the larvae will
feed on the provisions, and then create cocoons in which they will mature into adults later in the
summer or the next spring.

Design your garden so that there are flowers blooming nearby from spring to fall. It is important to note these bees will only sting if handled roughly (e.g. squeezed), and in the rare cases where this happens, their sting is similar to a mosquito bite.

Keeping your nest clean and dry is important. Nests should not be moved in the spring and summer if possible, as the developing larval bees could become dislodged from their food and die. Tubes should be replaced every year or two, and the box disinfected with a weak bleach solution if pests become a problem over time.
With your help, the local twig nestingbee populations can increase in number, and the whole ecosystem will benefit.

Note: Close to a third of our native bees nest in wood, including hollow- or pithy-stemmed plants. For example, small carpenter bees (Ceratina spp.), leaf-cutter bees (Megachile spp.), masked bees
(Hylaeus spp.), and mason bees (Hoplitis spp., Osmia spp.) are all types of twig or stem-nesters (Pollination Guelph).