Wednesday, June 23, 2010

Build a Mason Bee House in 5 Minutes

It is National Pollinator Week, and I figured a way to commemorate this was to build a mason bee nest box (more on this in a little bit). For Missoulians, a great way to celebrate this is at Thursday night's native plant sale with information about pollinators- including mason bees.

Unlike non-native honey bees that nest in hives with many others, native mason bees are solitary and each female builds her own nest. I think it's cute that although these are "solitary" bees they all nest right next to each other in communities, but evidently they have it worked out so they maintain their own identity. Anyway, they nest in cavities in logs, snags and decadent trees from woodpecker or wood boring insect holes. They also nest in hollow reeds and canes (like raspberries). As a result of the loss of native plants, removal of dead or dying trees, etc... many suspect that they are nesting site limited and by providing artificial nest sites (houses) we can help their populations.

Mason bee houses have been around for a while but I’ve been reluctant to build a house for them. Maybe it’s because I liken these houses to butterfly houses (that don’t work and cater toward yellow jackets). Or maybe it was because I thought by providing snags in the yard and or borer hole-filled aspen; we were providing more natural places for mason or other solitary nesting bees. So I did some research and in addition to a surprising amount of literature on the topic, I came across a great literature review that evaluated the efficacy of intervention (people trying to help out bees) on bee conservation: Bee Conservation: evidence for the effects of interventions Lynn V. Dicks, David A. Showler & William J. Sutherland Based on evidence captured at

Here is a brief summary:
Yes, mason bees do use the nest boxes (so they have a leg up on butterfly houses). However, in one study in California, introduced European earwigs and introduced European leafcutter bee species used the boxes, and in one instance these introduced species were more common in the houses than native bees.

What about plastic nest cavities or using plastic straws?
Nest boxes with plastic‐lined, plastic or paper tubes were worse for bees than houses with simpled bored wood nest holes. The main reason was mold and even increases rates of parasitism. This is not surprising that just drilling out wood holes more naturally mimics a natural hole in wood. Don’t use plastic or straws.

But the big question: Does this help populations on a larger scale, that is does it boost local populations? In reviewing several studies, the answer is unfortunately not really. The results were mixed, in some studies it seemed to help for a while in other studies there did not seem to be an effect. Kind of disappointing.
Despite the less than exciting results, I decided to go ahead and build some and see for myself. If nothing else, they are pretty fun to have in the garden and I am looking forward to checking on them and learning more about mason bees. But really, the thing that I think put me over the edge is I learned that these make great flicker feeders. I figured this out inadvertently since all the descriptions I read about making mason bee houses involved a phrase like “cover with chicken wire to keep birds out”. At first I was puzzled, since I knew no birds could get into the 5/16” diameter hole. But then I figured out what keeping birds out really meant.
This is the second installment of building things for your wildlife garden in 5 minutes (click here for the first- a suet feeder). This bee house is a great project to do with kids or just with the kid inside yourself. This is also a great project to make out of scraps you have on hand already, or a great use for recycled materials commonly found at Home ReSource.

  • 1/4” peg board*
  • 4"x4"x 12” or so
  • 1"x6"x18”*
  • 5/16” drill bit
  • Drill
  • Saw
  • Screws
  • clamps*


Step one
Cut 4x4 to size, cut the top at an angle to help shed water
Step 2
Use pegboard as a template for holes, align on 4x4, and drill 5/16” holes, about 3" deep (if you are using a 4x4- just don't drill all the way through the wood). The bees really don’t care if the holes are nicely arranged, and really you could skip this step of putting on a template, but I think it looks nicer.
Now, if you want, you are done. But, there is more if you are interested.

Step 3
Install top and back with screws- having the back on this allow for easy mounting on walls or posts. Now, you are done (again). All that is left is to install, and here are some tips:
  • Place 3-5 feet off the ground
  • Place east or south-east facing in a place where you can easily observe it
  • East is best so the little fellas can get all warmed up quickly by the morning sun
  • Once you install them, don’t move them until the winter
  • You can place several in various locations in your yard or give to neighbors for their yards
  • Try to place near a source of mud

Tuesday, June 22, 2010

Native Plant Sale and Insect Workshop!

Do you want skippers in your garden (like the one above)? Now is your change to buy their larval host plant- the prairie Junegrass (Koeleria macrantha ) at a fantastic native plant sale and insect workshop hosted by UM and the Montana Natural History Center.

Join a host of local experts to learn about gardening to attract pollinators, making mason bee nesting boxes, identifying common garden insects and learning to separate the harmful insects from the helpful.

The site for this workshop is the Nature Adventure Garden located out at Fort Missoula, which includes a 2-acre demonstration area of native wildflowers, trees and shrubs. It’s a perfect spot for pollinator observation as well as learning how to use native landscaping to attract pollinators!

Date: Thursday, June 24th
Time: 5:30 pm – 7:30 pm
Cost: $5 suggested donation.
Location: Nature Adventure Garden at Fort Missoula
Call 327-0405 for more information.

Teachers: 2 OPI credits available.

Monday, June 14, 2010

A new visitor to the garden

This morning I found a raccoon in the garden, and I'm not sure how I feel about it.
I consider raccoons a class 3 non-native species; this is according to my own little classification system (European starlings are a class 1, for example). Raccoons are not native to most of Montana, but are now widely spread across the state (this I have personally confirmed with roadkill observations). They are native to a small area in extreme eastern Montana, but they were never really common there. Their range has expanded throughout the state (and in the northern Rockies) in the last 50 years as a result of urban- and suburban-ization. Development, tree planting and food subsidies (garbage, pet food, and intentional feeding) has facilitated their range expansion. Raccoons are native to the US, and they have not been introduced by people (as far as I know), but since they are not native they have the ability to disrupt indigenous plant and animal communities and compete with other native animals.
They are similar in many ways to other non-natives we have in Montana, like Eastern and gray squirrels and house finches. All three of these are native to the US but not native to Montana, and all have been transported and introduced outside their native range by people. Squirrels have become a conservation issue and are really a problem (read more here , for example). On the other hand, house finches, which are native to the south western US but now occur all over the west, are merely a nuisance. I'm not aware of them being a conservation issue (as a little aside, since we stopped feeding sunflower seeds to birds, the house finches are uncommon in our yard).
So, I am not sure what to think of the new visitor. I will do some research and observation, and keep an eye the the little fellow for now.

Saturday, June 12, 2010

The ecology of yellow evening primrose in our backyard

There have been several great blog posts about pollinator plants and pollinator gardening, calling attention to both the good and the bad. (the latter post very articulately describes the problems with pollinator gardens). A while back I wrote about my disdain for the trend that was pollinator gardening. OK, disdain is way too strong, but you get the idea.

In honor of national pollinator week (June 21- 27), Kelly Senser from the National Wildlife Federation compiled favorite pollinator plants from gardeners from across the country (click here for the story). In this, I wrote about one of my favorite plants in our garden, the yellow evening primrose, (Oenethera flava). Tonight my wife and I watched as one of our yellow evening primroses opened- click here for a video of it happening (the action really picks up at 55 seconds).
Though the flower is gorgeous, large and showy, the real reason I like it so much is it offers a wonderful microcosm of wildlife gardening. In short, the primrose is moth pollinated, because it flowers at night. That is pretty cool in an of itself, and probably not that typical in the run of the mill pollinator garden. However, the neat thing is this is the host plant for a moth that does not feed on its nectar, since it is a daytime flyer: the five- line Sphinx moth, also known as a hummingbird moth. And where this whole story gets more interesting, and typifies the intricate plant/ insect relation ship is that even though the eggs and larvae are tied to the primrose, it needs something else to complete its life cycle- soft duff or sawdust.

In our yard it finds fresh, loose sawdust at the base of our aspen (Populus tremuloides)trees. The reason for this accumulation of saw dust is that the trees are invaded by the larvae of a long horned beetle- the aspen borer (Saperda calcarata). As the larvae tunnel through the aspen they force out sawdust that collects around the base. Also, as a defence, the aspen pushes sap out these wounds. The sap is a critical food source in the early spring for many species of butterflies that overwinter as adults like the mourning cloak or Lourquin's admiral (shown below feeding ion the sap of an aspen).
So, from this one example you can see how interesting and intimate the association of plants and pollinators are. Furthermore, you can also tell how unrelated some of these plants and animals are. Provide native species, and diverse assemblages and you will be rewarded with much more productive "pollinator" gardens than if you tried to plant a garden for pollinators.

Friday, June 4, 2010

Nesting, nestling and fledging update

There is a lot going on with nesting birds in our garden. We have northern flickers, black-capped chickadee, and red-breastered nuthatches in various stages of nesting and fledging in nest boxes in our small backyard. Here is a breif run down on the actvity....

Black- capped chickadees

The chickadees should fledge any time now- they are ready to go but have probably been delayed by this rain. By the way, thank goodness for the rain!

If you haven't done so already check out the inside of the nest box with our streaming nest camera. But you'd better hurry because they are about to fledge. Click here to go inside the nest box.

At the beginning of this posts is a short video my wife took of the outside of the box and one of the adults feeding the young. For those that only know the chickadees from the inside of the nest box, this view might be interesting.

One thing I am really excited about is that we will be able to capture the mysterious second clutch this year on camera. every year, the chickadees have a second clutch, even after a typically very fruitful first clutch. The second clutch is usually smaller, and takes less time to fledge. It has aways appeared that the young from the first clutch help in raising (or at least with the feeding), the second clutch. Hopefully, though we'll be able to learn a little more of what is going on. It is not really common that chickadees have two clutches, so I am excited to learn more.

Red-breasted nuthatches

These little fellas have been a bit overlooked this year, I am sad to say. Not that they care, but theirs is the only box in which we did not install a nest cam. As a result, we have been so focused on the chickadees and the flicker business, that these little guys have been almost ignored (not really, but relatively). Anyway, they should be fledging any day now, too, but without all the fanfare. One interesting thing to note with these nuthatches, is that there are nuthatches nesting in the nest box I installed at the 8th Street Pocket Park, which is just a block away. Every so often these two nuthatch factions defend their little territories, which is kind of neat.

Northern flickers

Wow, they have had an eventful spring. Here is a little story of their spring...
  • They excavated out nest box
  • They also excavated a cavity in a silver maple in front of my neighbors house
  • They laid eggs in the cavity in the maple
  • European starlings evicted them from their nest
  • The starlings are nesting in the tree
  • The flickers left the area
  • Last weekend the flickers returned to the nest box, and as of yesterday (June 3)have laid at least 2 eggs (in the photo below- kind of poor qualiy but it is a video capture).

I hope they can raise a clutch- it is getting late for them.

Once the chickadees fledge we will switch to the flickercam for nest box viewing. Exciting.