When we think of fall we often think of apple pie, football, volleyball, carving pumpkins, cool weather, and the beautiful display of tree foliage changing colors. As the different types of trees show their many variations of purple, yellow, red, brown, and orange we know that winter is close by. People often travel hundreds to thousands of miles to see the annual leaf color change in different parts of the U.S., but in Iowa we are fortunate that the beauty of fall is often close by, or just a few hours away from our back door.
The color we see when we look at leaves comes from cells called pigments. The green color we see every spring comes from the pigment called chlorophyll. Throughout the summer the pigments that give us fall colors such as orange, yellow, and brown are produced in the leaves, but they are hidden by the green chlorophyll. In fall as the days become shorter and cooler the production of chlorophyll slows down and eventually stops. As the green color disappears, the hidden pigments are unmasked and their beauty is released. Not all pigments are present in the leaves throughout the summer. For example, in species such as the sumacs, hard maples, white oak, red oak, and white ash the pigments that provide the eye-catching red and purple colors are actually not in the leaf until they are produced during the fall.
The timing, intensity, and quality of fall color varies each year throughout the state and even on the trees scattered in your yard or neighborhood. In general, fall color change occurs between the middle of September and the middle of October. There are many things such as temperature, moisture, rain, wind, and the availability of sunlight that impact the quality of fall color. Clear days, cool nights, and dry conditions promote high quality fall color. These colorful displays are often cut short by heavy winds, rainfall, and freezing temperatures which can actually kill leaf tissue and cause the leaves to fall early.
In Iowa when people talk fall color displays the northeast section of the state is often mentioned. This is a tremendous area to visit, but the beauty of fall color can be found throughout the entire state. There are many state parks, forests, wildlife areas, county parks, lakes, and rivers that provide an opportunity to enjoy Iowa's fall magic. There are a number of sources that can be utilized to locate scenic drives or spots in the area of your choice such as, local chambers of commerce, travel bureaus, county conservation offices, county nature centers, and Iowa State University County Extension Offices. Also, these sources along with the Iowa Department of Tourism can often provide lists of local fall festivals and recreational activities that are occurring.
The biggest challenge to a successful fall color expedition is venturing out when there is a good array of color. The thought of going over your favorite scenic hill and seeing nothing but brown, dull-colored, or leafless trees on the other side is every leaf color adventurer's nightmare. This apprehension can be avoided by calling ahead of your departure to see when the colors are peaking.
Many of the sources listed earlier such as the local chamber of commerce keep updated on the surrounding color display. Another good way to find out about your favorite area in the state is to check out the Iowa Department of Natural Resources fall color report or call their leaf-line at 515-233-4110. The message on this line is updated every Monday from the middle of September to the middle of October.
As you go out on your leaf color hunt, remember to call ahead, dress for cool weather, drive safely, and stop once in awhile to really enjoy Iowa's beauty.
If you would like to expand your fall foliage adventure outside of Iowa check out this national fall foliage prediction map.
Leaf Color Characteristics of Some Common Plants in Iowa
- Walnut: turns yellow in fall; one of the first to turn and drop leaves; one of the last to leaf out in the spring
- Red oak: brilliant red leaves in fall; color not as intense as some hard maples
- White oak: subdued red color of leaves in fall; turn brown and often stay on tree until new leaves begin to grow in spring
- Bur oak: buff to yellow; turn brown before falling
- Hickory: leaves turn yellow, then brown before falling
- Ash: leaves turn yellow; some have a purplish cast; leaves fall after walnut but earlier than oaks and maples
- Elms: leaves turn yellow, some turn brown before falling, others fall while still yellow
- Soft maple: leaves turn yellow and don't turn brown before falling
- Hard maple: brilliant red hues, red pigmentation of some leaves breaks down before falling
- Sumac: very bright red, often overlooked because it is a small tree confined to openings and edges
- Virginia creeper: bright red; very spectacular to when it grows on dead snags