Iowa State University Extension and Outreach
Hello Iowans! My name is Billy Beck - your new Forestry Specialist with Iowa State University Extension and Outreach. I hail from the Midwest, having earned my Bachelor’s degree in Forestry from Michigan State University, my Master’s degree in Forest Hydrology from Southern Illinois University at Carbondale, and my Ph.D. in Environmental Science (water quality emphasis) from Iowa State. I am honored to serve the people, forests, and water resources of “the land between the rivers” in my new role. I am also elated, as this position offers the opportunity to pursue my two passions – forestry and water quality! Feel free to follow our efforts on the ISU Extension Forestry webpage, Twitter and Instagram accounts.
In addition to covering all of Iowa’s 99 beautiful counties as an Extension State Specialist, I am also an Assistant Professor in the Department of Natural Resource Ecology and Management at ISU. Thus, I have research and teaching responsibilities that will act to inform my Extension programming. The role of Extension is to connect Iowa’s people, natural resource agencies and entities, and forestry industry with the research and resources of Iowa State University – empowering them to make their own informed decisions on the landscape. My ultimate vision is that trees, forests, and woodlands are valued in this state. Value at the state level, I believe, will come once forests (especially those lining waterways) are recognized for their ability to reduce nutrient loading and flooding in our streams and rivers. Value at the property level will come once all forest landowners, large and small, recognize the true potential of their forests – a powerful asset to be both utilized and protected. My Extension, research, and teaching efforts will be guided by this vision.
During my first few weeks, I have been reflecting on my new position in the context of the individuals who have served before me. This recent mulling, along with blaze-red sumac leaves signaling the end of another growing season, has me pondering legacies - how can we work to celebrate the past, while simultaneously striving for individuality and new directions? One activity that embraces this legacy concept also happens to be one of my favorite autumnal habits - growing trees from seed.
On a recent tour of a forested property along the Des Moines River corridor in central Iowa, the landowner and I stopped at large white oak (Quercus alba) nestled in the corner of a field. He told the story of how his only daughter had been married under that tree – the same tree they had spent countless hours together while she was growing up. This experience reaffirmed my belief that people place powerful sentimental value on individual trees and specific forested locations. I, for one, am notoriously guilty of this. A recent example occurred earlier this year as I moved my grandparents out of the house they had lived in for nearly 70 years. I put a bookend on this emotional experience by, you guessed it, digging up numerous American holly (Ilex opaca) seedlings from under the towering parent tree I had admired since I was a kid. These seedlings will become the legacy that connects me to that house, and the special times associated with it, for decades to come.
Collecting Seed and Testing for Viability
Although all native Iowa trees can be propagated from seed, albeit with varying es of difficulty, oaks (Quercus spp.) and black walnut (Juglans nigra) represent relatively simple starters to try your hand. Both are common statewide, and frequently produce abundant crops of conspicuous and easily collectable seed. Great resources to assist your tree and seed identification exist online. Acorns and walnuts ripen between September and October, and seeds should be collected from healthy, vigorous trees soon after they fall to the ground. Avoid collecting the very first seeds that drop (often seen in late August) as these may be aborted individuals. Parks, golf courses, and cemeteries often contain magnificent tree specimens, and their carefully manicured grounds provide for swift collection – making for an enjoyable autumn day with family of all ages. I’ve witnessed a few people armed with rakes and tarps fill a pickup truck with acorns in a few hours in these situations. Tools such as the Nut Wizard, Bag-A-Nut, and Stab-A-Nut also exist for larger-scale collection efforts. Forested locations, especially those with abundant leaf litter, can make collecting seeds a bit more challenging. The same tools and techniques may be employed in forested situations, however greater patience is be required.
Once collected, both acorns and walnuts should be separated from debris (e.g., grass clippings) and have caps and husks removed. Test both for viability by dumping the debris-free seeds in a bucket of water. Non-viable seeds will float and should be removed, while viable seeds will sink to the bottom. Indicators of non-viability may also include relatively light weight and density, cracks, mold, and small holes (caused by weevils). Soon after the float test, seeds of both oak and walnut should be removed from water, bagged (e.g., burlap, plastic) and placed in a cooler or refrigerator in preparation for fall planting or long-term cold storage (i.e., stratification).
Preparing, Storing, and Planting Seeds
Viable seeds from both oaks and walnuts can be planted in autumn, however, some notes on the breaking of dormancy and germination should be mentioned. The acorns of a number of oak species, such as white oak, will germinate immediately after planting in autumn. Other species, such as red oak (Quercus rubra), bur oak (Quercus macrocarpa), and black walnut require a specific period of cold and moist conditions in order to break dormancy and germinate. This process is known as stratification, and can range between 30 - 90 days for oaks, and 90 – 120 days for black walnut. When an acorn or walnut drops in autumn, the Iowa winter typically handles this process naturally. However, you can also stratify seeds yourself. To stratify acorns, place in a sealed plastic bag, coffee can, or similar storage container, and store in the refrigerator (just above freezing) for the required stratification time. Following this, acorns can be removed from refrigeration and planted in spring. Walnuts can be stored in similar containers, however, be sure to add a moist mixture of sand and peat moss inside the container prior to refrigeration. Following the 90 – 120-day stratification period, walnuts can be removed and planted. If you lack refrigerator space, seeds of both oaks and walnuts can be stratified outside in buckets, pots, or similar containers. Ensure containers are protected from extreme temperature swings by insulating with a thick coat of mulch or leaves. Containers may also be buried up to the rim, and insulation added on top. Acorns should be planted at a depth of one-half to one inch, and walnuts at a depth of one to two inches.
This autumn, I encourage you to think about the trees or forested areas that have special meaning in your life. Grab your family, pick a beautiful day, and head outdoors to start a legacy!
Photo 1: Seed collection is one of my favorite fall activities, and is an activity that can help connect generations of family members. Butternut (Juglans cinera) seeds with husk shown. Photo credit: Billy Beck
Photos 2 and 3: A bur oak seedling and the magnificent parent tree which yielded the acorn. Photo credit: Pat Beck