Iowa grown trees and shrubs provide many benefits. The single plant that is a tree seedling soon becomes an ecosystem unto itself, with animals and other plants living in it and on it. If you plant many trees, closely spaced, you have the beginnings of a forest. Many different animals and plants will live there and great benefits will be provided. When planting trees it always best to utilize native tree and shrub seedlings from a locally adapted seed source because:
- They are better adapted to Iowa's extremes in weather and to Iowa planting sites
- They provide superior native wildlife habitat
- They are less likely to be stressed than none native plants
- They are more resistant to insect and disease attacks
- They are a link to Iowa's natural heritage
The further you move tree or shrub seedlings north or south from their native locally adapted range the more likely they will be to develop forest health and mortality problems. For example, bur oak's native range stretches from southern Texas to southern Canada. Even though it is native to Iowa, it would be a poor practice to plant bur oak seedlings (or any other species) from a Texas or even a central Missouri seed source in Iowa. This is because the bur oaks in those areas have adapted over the centuries to a much more temperate climate than we have in Iowa. They simply will not tolerate our weather and site conditions as well as our naturally adapted Iowa bur oaks. The best way to insure that your seed source is Iowa adapted is to purchase seedlings from Iowa Nurseries for your tree and shrub plantings.
Generally, people plant trees to grow forest products, to increase or improve wildlife habitat, to protect the site from soil and water erosion, and to improve the intrinsic beauty of a landholding. The nice thing about tree planting is that even though you may be focused on one of these goals, you receive some of the benefits of the other goals as a bonus. That is, when you plant trees for forest products, you get aspects of wildlife habitat, beauty and environmental protection right along with the products. Still, you should pick and choose the species you plant according to your land management objectives and your planting site.
Iowa has the enviable distinction of having the right soils and climate to grow some of the finest hardwoods in the world. Iowa grown black walnut, for example, is unsurpassed. When planning a tree planting on upland sites or sites with rich soil in which clear lumber and beautiful veneer are your objectives, choose red, white, black, and bur oak, black cherry, and black walnut. When planning a tree planting on bottomland sites plant silver maple, cottonwood, sycamore, bur oak, swamp white oak, and pin oak. These same trees, except for walnut and cottonwood, are also best for fuelwood plantings.
Another product for which trees are grown and harvested in Iowa is Christmas trees. The best species to plant for Christmas tree production are Scotch and white pines, although interest in firs seems to be increasing.
Wildlife habitat has two aspects, food and shelter. The usefulness of a tree or group of trees depends on many factors, including size, condition and spacing. Generally, trees become useful to wildlife when they become large enough to produce food and then increase in value as they become older and larger, because they produce food in larger quantities and begin to provide shelter for birds and animals that live in cavities.
Generally the same species that produce fine hardwood products are also valuable wildlife species because they produce acorns and nuts, collectively called “mast”. These species, as they age may also develop cavities that birds and animals can use for shelter. Other tree species of value to wildlife include aspen (buds used for food), silver maple (mostly shelter), common choke cherry (food and shelter), pines (shelter and roosting sites), red cedar (food and shelter), and crab apple (food). A large variety of shrubs such as wild plum, ninebark, dogwood, hazelnut, elderberry, arrowwood, nannyberry and serviceberry can also provide food and shelter for wildlife.
Trees protect the environment by easing summer and winter temperatures, by cleaning water, by reducing soil erosion, by reducing noise and by filtering air.
An acre of Iowa forest on a summer day can transpire over 1,600 gallons of water. This cools the surrounding area by a much as 5 to 15 degrees. This effect, when combined with placement of trees around homes for shade, can reduce air conditioning demands from 10 to 43 percent.
In the winter, windbreaks of conifers can reduce heat loss from 5 to 40 percent around farmsteads and rural residences.
Trees clean water in two ways; by preventing soil erosion, either by holding soil in place or by trapping it as it is borne overland by wind or water and by trapping nitrogen and phosphorous, thus reducing the occurrence of these two elements in drinking water. Trees planted along waterways can be very effective in reducing the amount of soil washed into streams and rivers.
The capacity of trees to reduce noise is often used in cities and towns to diminish highway and other noise.
Trees clean the air by using and storing carbon dioxide and by trapping dust and other airborne particles in their foliage.
“I think that I shall never see a poem as lovely as a tree....” So begins a poem by Joyce Kilmer that expresses the ways trees add beauty to their surroundings. All trees are beautiful, some even magnificent, but when we speak of beautiful trees, we are sometimes thinking of those trees that have showy flowers or fruit.
These could include black locust, buckeye, catalpa, service berry and most of the fruit trees; apples, crabs, peaches and pears. Some trees are beautiful for their shape and are used with good effect in landscape situations.
So, before you begin your tree planting endeavor by ordering seedlings or gathering seed, take some time to decide what you want from this undertaking you are about to begin. Good sources of additional information are District Foresters, County Conservation Board personnel or County Extension agents.