Healthy trees make healthy lakes
By Sue Schneider
From Living on the Lake magazine
When it comes to restoring natural shorelines, Phil Puestow has a lot of experience. As a forestry technician for the Wisconsin Department of Natural Resources, he is charged with managing 33 state-owned islands on 17 Oneida County lakes with an eye for future generations.
He spends a lot of his time restoring vegetation along those miles of shoreline, planting native trees and bushes. “On some of the more developed lakes, those islands are the only natural shorelines there are,” he explains.
“Where native plants thrive, animals, birds, fish and insects flourish. Diverse natural plantings are the best way for lakes to stay healthy and vibrant. It may take many years for trees to mature and make good habitat, but we do it for the future ecosystem, and for our children and grandchildren to enjoy.”
The history of human settlement on Northwoods lakes tells an alarming story, according to Phil. “Studies show us that a typical lot-sized piece of undeveloped, natural shoreline lets about two pounds of sediment flow into a lake during the course of a summer,” he says. “During the 1940s, when people started to build cabins and cut viewing corridors to see the lake, that sediment flow was about 20 pounds.
“Now, with larger homes, paved drives and extensive lawns, that same sized lake lot will allow 90 pounds of sediment into the lake. That has a devastating effect on the health of the lake,” he says. “Look at lakes in the southern part of our state and you will see the results: a lot of development for people, but very little – if any – left for wildlife.”
The one big key to reversing this trend, Phil says, is planting trees and vegetation on shoreland property. “It not only stops the run-off pollution and supports wildlife on the land,” he says. “It sets in motion all kinds of beneficial actions in the lake itself.”
Trees = better fishing and hunting
Trees sprouting up on the shoreline will naturally lean over the water to get the most sunlight they can, he explains, sending roots far back into the bank like a lever. This creates shore stabilization and shade that keeps the water cool and facilitates high oxygen concentration for aquatic plants that support fish and waterfowl populations.
Insects will gather there in the cover of the vegetation and provide food for fish and other aquatic species. Trees that fall into the water become woody habitat for improved fish growth and reproduction, and autumn leaves will sink to the bottom of the lake and deliver nutrients.
Even dead and dying trees are beneficial. “Insects will invade a weakened tree,” says Phil, “and then woodpeckers will come in to carve out nesting cavities and homes from other animals, birds and bats. Of course, whenever a tree dies, we have to look around for human impact. Have we disturbed the soil by digging or paving? Have we disturbed the canopy?”
The life of a tree, like an ecosystem, is a delicate balance. Between changing weather conditions, insects and disease, the struggle to grow and reproduce while competing with surrounding trees for sunlight, space and water means not all trees will make it.
Protect existing trees
Phil knows from his experience managing dozens of islands that the main enemy of shoreland vegetation is people. “Fishermen cut down bushes that are in their way,” he says. “Campers cut trees for firewood, or peel the bark off birch trees to kindle fires. Boaters will tramp on the shoreline until the ground is so hard, no seedlings can survive.”
The more fragile state-owned islands are closed to visitors, some are for day use only and some allow one-night camping. All are vulnerable. “It’s not easy,” says Phil. “Sometimes I’ll put up signs and in a couple of days they are torn down because people don’t like what they say. As a general rule, if you don’t see any signs that allow visitors, assume that island is closed.”
His advice for property owners who want to restore their own shorelines is to tread lightly. “Impacted soil is hard on vegetation. It’s best to try to keep people and pets from walking there. Often, shorelines are very rocky anyway, and helping seeds get a foothold is a challenge.”
Raking leaves on natural shorelines is also not always good. “At first, it can be a way to expose soil to seeds and get light down to small plants,” Phil explains. “Once things get going, though, leaves left on the ground will provide cover and keep soil from drying out.”
One of the most economical ways to get trees established is to take advantage of the DNR annual seedling sale. “There is a wide variety of trees and bushes available,” says Phil. “They are small seedlings, which are great for tucking into shoreline areas; no digging is required, just push in a planting spud and drop the roots in.”
Many things need to be considered before planting, though. Soil acidity and moisture, presence of existing vegetation and the amount of sunlight available in a location will either spell success or failure for seedlings. “Look around at what is already growing in your area,” Phil suggests. “That will tell you which species will thrive there.”
Seedlings can be placed near older trees, according to Phil. “The best place is right along what we call the ‘drip line’ or the edge of the canopy – right where rainwater drips off the leaves. You can’t really rely on just rain for moisture, though. For the first season or two, it’s very important to water seedlings thoroughly and regularly. Fertilizer is generally not needed.”
Sun-loving trees include such species as birch, aspen and red pine. “Birch are beautiful and fast growing,” says Phil. “But they don’t last long. They die from the inside out and from the top down. The bark will hold them up, but when they fall, they go down hard.”
White pine, maple and oak are more shade tolerant, but quite slow-growing trees, according to Phil, requiring patience. “With these species, you’re looking at a 30- to 100-year investment. It might not reward you in your lifetime, but future generations will really enjoy them.”
Larger, older tree specimens require more elaborate planting methods and should be planned carefully. All young trees should be protected with some sort of fencing, according to Phil, that takes into account all dangers.
“Deer will browse on just about anything,” he says. “A planting tube is perfect to surround young trees for the first couple of years. They must be placed carefully, though, and securely fastened to a stake. Watch out for tipping which can open up a spot at the bottom for mice and voles to climb inside. They will nibble on the bark and kill the tree.”
For more specific information on tree planting and to obtain an application for the annual seedling sale, visit dnr.wi.gov/topic/TreePlanting/. Ordering begins in October for spring delivery, but planning for a greener future for area lakes and neighborhoods can begin today.
Sue Schneider is a freelance writer who lives in Rhinelander. Her articles also appear in Northwoods Commerce and Northwoods ‘boomers and Beyond magazines.