If there's a four-letter word in gardening, it is d-e-e-r.
Bambi and Rudolph not-with-standing, this is the season when anyone trying to
grow much of anything outdoors begins to really get twitchy.
Or, at least those of us who haven't yet hammered our stakes
into the ground and strung up our netting, burlap-wrapped our specimen plants,
or sprayed stinky concoctions on our plants-all in an effort to ward off deer
from our yards as winter moves in.
While my 4-year-old is gleefully scanning our yard for
Rudolph, I am glowering at his cousins, the North American White-tailed deer, Odocoileus
virginianus. They are, of course, eyeing my unfenced, defenseless pines and
pfitzers, plus anything else in the winter landscape that appeals to their
taste buds.
The problem is there really isn't a "deer resistant plant"
out there. As Brad Roeller, manager of the grounds and display gardens of the
Mary Flagler Cary Arboretum in Millbrook,
N.Y., recently pointed out at my
local garden club meeting, deer will taste, and possibly devour, any plant
sooner or later. It's a matter of hunger, curiosity, and sometimes changing
dietary needs.
Roeller knows his plants-and his deer-from 35 years of
working on the arboretum grounds, now part of the Institute of Ecosystem
Studies (IES), and more recently 10-plus years of formal studies of what does
and doesn't work to protect vegetation from deer. The proper term is "deer
browsing." A single deer consumes about 3,000 pounds of greenery a year. "Browsing"
sounds too genteel a word for that kind of appetite.
Deer cause more damage to our crops than any other species
of wildlife. They affect at least 40 percent of all of our nation's crops at
some level, based on Pennsylvania
data, Roeller said. Some $250 million is spent per year to replace
horticultural plants damaged by deer; $10 million alone in New York state. I'm too depressed to find
out the Connecticut
statistics, but I'm sure UConn or someone else has them.
Now, we could get into all kinds of debates over who was
here first, deserves to eat what, and why can't we just all get along. As would
anyone who takes an ecosystem approach, Roeller stepped back and presented the
bigger, longer-term picture.
Deer damage to landscapes is a fairly new phenomenon in
southern New England, he said, largely because
of our changing land uses in the past 50 years. Back when New
England was an agricultural region and our trees fueled industrial
development, there wasn't a deer problem.
Or, the problem Teddy Roosevelt and others saw was one of
possible deer extinction, Roeller said. As the Northeastern forests came back,
it wasn't until the 1920s or ‘30s before deer needed to be managed in some
areas. Dairying and meadows kept the population at the forested edge of the
fields. However, the spreading forest
canopy and encroaching housing developments have created prime deer
habitat.
Today, we have more than four times the woodlands as during
the Civil War era, Roeller said, and more deer than ever reported.
In 1983, a forestry census reported 600,000 deer in the 15
Northeastern states, he said. By 2003,
the same sampling methodology turned up more than 3 million deer. In many
areas, the number of deer is well over the biological carrying capacity-the
tipping point when emerging seedlings can't survive. Bottom line: The more
deer, the less diversity in a forest. Other wildlife, including birds, gets
crowded out, and the vegetative balance goes out of whack and invasive plants
have an easier time taking over.
The kicker: A local herd of deer can increase as much as 50
percent in one year in the absence of mortality. Mortality for most New England deer comes with a four-wheel encounter or old
age.
Back to the point: What is a gardener to do? Give up and
plant plastic trees and shrubs? Although Roeller considers Nov. 1 his deadline
to determine if it's going to be an 8-foot fence kind of winter, or one where
repellents will handle the onslaught, he has practical advice for us laggards.
Deer are creatures of habit. It's not a matter of trying to
keep them out of your yard and flowerbeds just certain times of the year. Make
it an unpalatable place year-round. That means judicious fencing and a rotation
of repellants year-round, especially after planting something new.
Deer are a maternal lot-a doe and her offspring may never
leave a 200-acre woodland if she decides the conditions are right. Dominant
moms will jealously protect their turf from other broods and avoid areas they
distrust.
The point is to try not to let a resident deer family move
in, he said. If you see new deer around, that means something has happened to
the local dynamic. Time to erect tall fences and start being smelly to ward off
new neighbors.
Roeller has tested just about every commercial and homemade
deer spray, hung soap bars on tree branches, and even put dabs of peanut butter
and rolled oats on electrical fences. This last approach works particularly well
after a wet night. Tying strips of white fabric on wires strung about deer-rump
height also simulates another white tail running out of the area, away from
danger.
He has seen some of the best commercial sprays fail when
deer are hungry-after a long winter or during a drought. Other times, some of
the less effective ones have worked well, such as when there's a good supply of
acorns on the ground, or plenty of forest vegetation. Either way, plan to spray
every four weeks in the winter and every two in growing season. Our winter
challenge is that temperatures should be above 40 degrees all day, and it
should be dry, for good spraying conditions.
An inexpensive home brew Roeller recommends is to mix one
egg with ½ cup whole milk, add 1 tablespoon each of cooking oil and dishwashing
soap-he prefers lemon-scented products-and add to a gallon of water. Spray
vulnerable plants every 10 days. The key to this is putrescent eggs. Throw in
some hot pepper sauce and a couple of drops of rosemary oil for good measure.
Rotate spray concoctions every third time, just to throw the
deer off track.
Just don't send the deer into my yard.
For more information, visit IES at www.ecostudies.org.