This year's No. 1 garden plague scampers on four feet and is cute as a button. Several consecutive years of unusually large acorn and other wild nut crops has produced the biggest squirrel population boom in memory. And the increase in chipmunks is greater yet, since its narrower diet ties its fortunes even more closely to the acorn crop.
Probably no wildlife is more popular with urban dwellers and at the same time more of an animal nuisance than the gray squirrel. The current population explosion is winning it more foes than friends, since a crowded squirrel is not a well-behaved squirrel. Torn-up lawns, flower pots, vegetable gardens, and bulb plantings have most gardeners frustrated with the furry critters.
"Man, they're horrible," said Fox Hill Garden Club member Beth Benjamin of Dover. "They tear up everything. I think one chipmunk is living in my downstairs basement ceiling vent. And the squirrels are fearless. You can walk right up to within 3 feet of them. They're digging up my lawn right now."
"This is the worst year ever. Absolutely," said Carlo Obligato of Newton. "They've eaten all my tomatoes. All of them. They eat them red. They eat them green. I want to know how the nut crop is this fall. If there's another bumper crop, I'm not growing tomatoes next year."
Trees don't produce the same amounts of seeds each year, instead following their own boom-bust cycles of reproduction. Perhaps because of favorable weather conditions, trees have produced bumper crops of wild nuts. Acorns, beech nuts, hickory nuts, maple seeds, and pinecones have all had several big years, said Marion E. Larson of the state Division of Fisheries and Wildlife. This has a profound effect on acorn-eating animals such as deer, wild turkeys, skunks, bears, racoons, and opossums, but especially on squirrels and chipmunks.
"If there's an abundant food supply, more survive and more start to breed," said Larson.
Foxes are doubly blessed because they eat both the acorns and chipmunks that eat the acorns. The nut-fest also provides more prey for coyotes and owls. Everybody's happy but the gardeners.
Squirrels produce two litters of about four young a year. It's possible that the first little ones from last spring are already breeding, too, because well-fed gray squirrels can become sexually mature in just three months.
The boom may start winding down soon, though, because this fall's nut crop "is nothing like last year's," said Tom Ward of Harvard's Arnold Arboretum. "I have not seen the production that I have in other years."
In that case, said Chris Leahy of the Massachusetts Audubon Society, "You get a year with a lot of young squirrels running around saying the cupboard is bare. There will be gray squirrels creamed all over the streets. They are probably not wandering aimlessly, but dispersing looking for food."
At this point, the so-called "suicide squirrels" whose bodies now line every Bay State roadway are simply youngsters who haven't lived long enough to acquire the squirrel wisdom of their elders, who have a healthy suspicion of streets and cross over them on telephone wires when possible. Most of the young'uns won't live long enough to catch on.
So maybe the squirrel population will thin out and we can plant tomatoes next year. But what about this year?
This is probably not the best year for planting the rodents' favorite bulbs, tulips and crocus, though there are precautions you can take. These include buying hardware cloth, chicken wire, or treated rocks to layer under and above bulbs when planting. Some gardeners soak bulbs in Deter or Ropel before planting, while others sprinkle the topsoil with cayenne pepper. Planting bulbs deeply will also help. Large tulip bulbs actually perform better when planted down to 18 inches deep. Rodents generally find snowdrops, daffodils, leucojum, fall-blooming crocuses (colchicums and sternbergias), squills, chinodoxias, camassia, fritillaria, hyacinths, grape hyacinths, and alliums unappetizing.
Population pressure promises to spur squirrels to new heights of ingenuity at the backyard bird-feeding station. So this may be the year to invest in one of the many squirrel-resistant feeders. The shop at the Massachusetts Audubon Society headquarters at Drumlin Farm, 208 South Great Road (Route 117), Lincoln, sells several kinds, though none are guaranteed. The motorized $115.50 Droll Yankee Flipper spins when a squirrel gets on board. The Droll Yankee Tipper, Whipper, and Dipper ($84-$114) are all designed with collapsible perches or trays. Baffles come in several models, starting at $15.95 (781-259-2210, email@example.com). The secret to these, says "Hand-feeding Backyard Birds" author Hugh Wiburg of Wilmington, is to place one immediately above a hanging feeder and a second baffle at least 15 inches above that. The feeder should be at least 4 1/2 feet above the ground and 10 feet from tree trunks and other jumping-off points.
Live trapping makes sense if you are trying to move squirrels or chipmunks who have taken up residence in your house. But first you have to find and block their entryways. When squirrels invaded her eaves, Benjamin found that stuffing the openings with rags soaked with ammonia or bleach worked. "They definitely went away and we were able to patch the holes." Many frustrated gardeners capture outdoor squirrels in live traps, stick them in the trunk of their car and take them for a one-way ride, either to the local pond for a last swim, which is legal, or, more often, to another neighborhood, which is not. Since this seems to make no dent in the squirrel population, scofflaw gardeners often spray a burst of paint on their captive's bushy tail to reassure themselves that the same squirrels aren't finding their way back home. They don't have to. Others move in immediately.
"The legalities are that you may protect your property from damage and you are legally allowed to trap the squirrels with box traps," said Larson. "You can't use poison and you can't use leg-hold or body-ripping traps. But once you have the animal, what do you do? There are only two options: releasing the animal back on your own property or killing it. You cannot legally transport animals to other properties and release them because it has the possibility of spreading disease. And it just spreads the problem."
"Some people say, `I don't want to deal with trapping and killing them. Let me hire someone else to do it for a fee,"' Larson said. "Our agency licenses problem-animal control agents. They have to take an exam and a couple of classes." (The website mass.gov/dfwele/dfw/dfw_pac.htm contains contact information on licensed animal-control agents and information for property owners about their options and the law.)
If you're a sportsman, you might be interested to known that the squirrel-hunting season for Worcester County and Western Massachusetts opened Sept. 13. It begins Oct. 16 in the eastern part of the state. Both hunting seasons end Jan. 1. Squirrel hunting is popular in some parts of the country, as is squirrel cuisine. Young squirrels are reportedly tasty when fried while older ones are better stewed.
The other option, of course, is that you just coexist with these animals. "Some people say that's not that bad a deal. It's a question of the tolerance level," said Larson. "The mere presence of a squirrel does not make it legal to trap and destroy them. You need good evidence that the squirrel has destroyed property."
That evidence is easy to find. Beth Benjamin has seen chipmunks sitting on the patio tomato cages eating her tomatoes, and one woman called Larson while watching a squirrel pulling plants out of her pots, taking one nibble from each and then digging up the next one. "But the most bizarre call we got this year was from a Shakespeare production on the Boston Common this summer," said Larson. "Squirrels were chewing through the wiring and falling off the scaffolding onto the stage or audience during the performance. I didn't have a solution."