Part of our organic farm’s integrated pest management plan calls for the use of hosted beneficial birds as natural predators. Earlier this week I asked a couple of friends and folks at the Tennessee Wildlife Resources Agency (TWRA) for some advice and was reminded about the amazing Purple Martin.

Growing up in the South, I remember Purple Martin houses on several farms. I never really thought there was a functional reason for hosting them, and later was convinced all they ate were mosquitoes.

I was wrong. State Zoologist David Withers sent me this great one pager from the Purple Martin Conservation Association that basically tells me the Purple Martin is one of nature’s best bug zappers. Check out TWRA’s wonderful online resource on common birds and how to host them.

Even if you are not an organic farmer, hosting Purple Martins can dramatically help reduce any flying insect pest on your property while reducing the use of chemical sprays and inviting a little of nature’s perfect aesthetic back to your home life.

We got two 16 family houses, both made in America, at our local Tractor Supply Company (photo: Vince snaps a Purple Martin house together). We’re using cut cedar posts from the property and will open the houses March 31 or as close to the time we begin seeing younger Purple Martins.

Here are a few points we’ve learned through some voracious reading over the past couple of snow days:

• Purple Martins overwinter in Brazil and return year after year to the same nesting location.
• They live exclusively in human made housing (East of the Rocky Mountains)
• Houses must be over 10 feet off the ground, a minimum of 30 feet from a human dwelling (120 feet maximum), about 45 feet from any tree or bush and have nothing touching the pole, including support wires. Nothing around the housing can be taller.
• Entry holes must be a specific dimension or competing birds become a problem (3 inches wide and 1 3/16 tall).
• Purple Martins prefer white colored housing.
• To attract a colony you must open the house when last year’s young return – 3 weeks after the first adults arrive. In Tennessee, adults arrive March 1-15. Adults will also colonize, but you must be persistent to scare off competing birds.
• Purple Martins diet includes “dragonflies, damselflies, flies, midges, mayflies, stinkbugs, leafhoppers, Japanese beetles, June bugs, butterflies, moths, grasshoppers, cicadas, bees, wasps, flying ants, and ballooning spiders.”
• Once hatched, Purple martins develop in about 30 days.
• You can handle the chicks to manage the nests – parents do not mind human handling or scent.

Tim warned me it was just a matter of time before the cute deer became a nuisance. The tips of this winesap (W4) are all nibbled by deer.

I’ve been doing a lot online reading to get ready for this.

Cage: I’m testing fencing one tree after reading about it and determining it’s probably the most fail safe solution. The problem with it is the cost, labor (work adds up per tree) and the way it looks. But it works. I placed 5 feet tall fence about 2 feet above the ground giving me 7 feet of protection.

Contraptions: The next thing I found was something that I still want to try. It’s a solar powered water sprayer that uses infrared motion senors to detect animals and then sprays a burst of water. It’s expensive, but the other problem I see with this and the version that uses a hose is that they can freeze in the Winter.

Scents: This seemed like the most ridiculous category consisting of people swearing by sprinkling human hair, urinating, hanging bags of soap or dirty clothes in the trees. People swear by them probably up until the have to collect this stuff.

Sprays: There are all kinds of sprays, but I’m limited to organic ones. There are plenty of them, but most only last a couple weeks. It’s easy to apply, and it’s also cheaper to make your own. So that’s what I did. I just mixed the following ingredients and used a hand-held sprayer to coat the trees and the blueberry bushes. I’ll probably do it regularly and see how it goes.

• 3 gallons of water
• 5 tablespoons of ground cayenne pepper
• 4 eggs whites

Smokehouse: I’m not giving up on this option. We’d have plenty of turkey and venison.

UPDATE 12-6-12: It rained the day after the first application and I saw fresh damage by deer to two more trees. It looks like we’re going to cage them.

UPDATE 12-10-12: After finding significant evidence of damage the day or two after application of the cayenne pepper concoction, including one of several damaged blueberry bushes literally ripped from the ground, we caged all the apple trees and purchased a solar-powered electric fence for the blueberries.

My thinking on scents and taste deterents is that consumers are easily tempted to want to out smart deer with these products, but if you are serious about protecting your orchard you’ll fence your trees and bushes. So, do it right the first time.