At the well attended April meeting, members gathered to learn about important gardening issues from Dr. Dean Krauskopf. Dean began with a presentation then handled lots of questions from those present.
Dean talked about lead. Lead leaches under acidic conditions. If you ask about lead when doing a soil test, MSU will test for it. Lead paint was banned in 1978. There could be lead in the soil near a house built before then from lead paint. The lead, measured in parts per million (PPM), might dissipate quickly as you move further from the house. Lead is primarily taken up in the roots so do not grow root crops in contaminated soil. It is important to wash all garden produce well before consuming.
Dean pointed out that when a chemical, that is effective when used properly, is effectively eliminated as an option, the absence of a tool might create other problems. People may resort to using stronger or less effective chemicals that might be detrimental to pollinators or beneficial insects or might require multiple applications or more careful timing. One less option means one fewer tool to tackle a problem.
Dean talked about oak wilt, a problem we often perpetuate ourselves by pruning or cutting when beetles are out, which is anytime that the ground is not frozen. There is no cure or treatment except the destruction of infected trees. There is also no chemical control for Thousand Cankers Disease. Dean talked about IRAC, the Insecticide Resistance Action Committee, bees, heating degree days and accumulated chilling hours, that it's okay to prune roses now, how our 2015-2016 temperature swings are problematic for plants, micro environments, the benefits of raised beds, interrupting the life cycle of Viburnum leaf beetle, grass fertilization treatment programs, rubber tire compost, pre-emergent, dogs, peonies and rhubarb. It was a full night of science and sensible information.
Dean provided a variety of links to resources:
Lead levels of edibles grown in contaminated residential soils: a field survey, http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.525.4560&rep=rep1&type=pdf
Effects on human physiology, http://www.atsdr.cdc.gov/csem/csem.asp?csem=7&po=10
NEONICOTINOID INSECTICIDES & POLLINATORS
Insecticide Resistance Action Committee, http://www.irac-online.org/
Thousand Cankers Disease, http://www.thousandcankers.com/
Midwest Invasive Species Information Network, http://www.misin.msu.edu/
Midwest Regional Climate Center, http://mrcc.isws.illinois.edu/
Calculating degree days, http://fyi.uwex.edu/hort/files/2014/11/Degree-Day-Calculation.pdf
Garden Professors' Blog, GardenProfessors.com
Native Plants & Ecosystem Services, http://nativeplants.msu.edu/