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On July 16, 2016

Extension Soil Fertility Specialist Doug Beegle tells us there have been several reports of potassium (K) deficiency recently. With regular soil testing these can usually be avoided. It is important to remember that forage crops remove very large amounts of K from the soil which can deplete the soil rapidly. Corn silage removes around 8 lb K2O/ton and most hay crop remove 40-50 lb K2O/ton. Thus maintaining K with regular manure or fertilizer applications based on soil tests is critical.

Also, realize that while K deficiency in plants is often due to soil K deficiency, other factors like soil compaction can also result in a plant K deficiency even in a soil with adequate K. This year it seems that the deficiency is more common in areas that may have been wet around planting time resulting in compaction and now the very dry weather is making the situation worse as the plants are struggling to grow roots and thus also struggling to take up adequate K. A common question this time of year with K deficiency is whether it will help to apply K to growing corn. It is getting pretty late now, but if the corn is not too tall to broadcast K fertilizer, there is a good chance that adding K will help the crop recover at least some from the deficiency. Besides, if the soil is deficient, a K application is necessary at some point anyway, so applying it to the growing crop may help that crop, but regardless it will begin building up the soil K for the future.

However, the very dry weather we have been experiencing lately will work against this in-season added K being taken up by the crop, because it takes some water to dissolve the K and move it into the soil and also the dry surface soil will have fewer actively growing roots near the surface where the added K will be, because K is relatively immobile in the soil. Thus, this will be more likely to be successful in long-term no-till fields with good residue which helps maintain moisture and active root growth near the soil surface. Before making a K application, check the soil test to make sure the deficiency in the crop is due to low soil K and not some other soil limitation. Applying K to a soil already adequate in K but limited by some other soil factor, such as compaction, will be of little help. Applying foliar K to deficient crops will have little lasting effect. Most crops take up 200 lb K2O or more per acre. A foliar application often only applies a few pounds of K, making it very difficult to supply a significant amount of the crop need for K foliarly.

Finally, talking to people about this, there has been some confusion in diagnosing K vs N deficiency. Both occur on the lower leaves of the plants, but N deficient leaves will turn yellow and eventually brown starting at the tip of the leaf and going back the middle of the leaf (N). Potassium deficiency, on the other hand, will start at the tip of the leaf and go back the edges of the leaf (K).

TO LEARN ABOUT STARTING A SMALL FARM BUSINESS

Thinking of creating a business on few acres of land (or your backyard garden) in 2017? If so, Exploring the Small Farm Dream can help you determine if your vision could become a reality. This course, developed by the New England Small Farm Institute, will be offered in a three-evening series from 6:00 to 9:00 p.m. on Tuesdays, August 9, 23 and 30, 2016, by the Penn State Extension Agricultural Entrepreneurship Team in cooperation with Horn Farm Center for Agricultural Education, in York, PA.

Whether you envision owning a farming or food business – selling cut flowers, growing heirloom tomatoes, raising free-range chickens, or making goat cheese – this course will provide the tools to start making that dream come true. Participants will discuss current opportunities in small-scale agriculture, explore objectives, assess personal and financial resources, conduct preliminary market research, and develop an action plan for pursuing their entrepreneurial interests.

The course will be held at the Horn Farm Center (4945 Horn Road, York, PA 17406) on Tuesday evenings, August 9, 23, and 30, 2016, from 6:00 – 9:00 p.m. A registration fee of $125.00 per person, $200.00 per couple/partners covers all classes and materials. To register for this class, visit http://extension.psu.edu/events (search for event link using the keyword “Exploring”) or call the Penn State Extension Dauphin County Office, at (717) 921-8803 before Friday, July 29, 2016; class size is limited to the first 16 registrants. For more information concerning class content and activities, please contact Extension Educator Winifred McGee at wwm1@psu.edu<mailto:wwm1@psu.edu> or by calling (717) 921-8803.

TO LEARN ABOUT PROFESSIONAL TURFGRASS MANAGEMENT

Penn State Turf and Ornamental Field Day is our chance to show you the results of turfgrass research designed for golf course superintendents, sports turf managers, and lawn care operators; and provide tours and hands-on demonstrations for landscapers, nursery operators and others interested in ornamental horticulture. The event will be held on Wednesday, August 10 on the Penn State main campus. What was formerly Penn State Turfgrass Field Day, has been expanded to include a Core pesticide education program from 9:00 am to 10:00 am, followed by morning breakout sessions on pests of ornamental plants (pest walk), load procurement, and a green roof tour (10:30 to 11:45 am). In the afternoon program, attendees can participate in tours of turfgrass research at the Joseph Valentine Turfgrass Research Center from 1:00 to 4:00 pm, or three breakout sessions dealing with ornamental ground covers, native plants, pollinators, soil and disease diagnostic lab tours, and a tour of the Penn State Arboretum from 12:45 to 4:00 pm.

The turfgrass research component of Penn State Turfgrass and Ornamental Field Day will feature a variety of turfgrass field research demonstrations and plot tours. Turfgrass field day is a great way to learn about the latest findings in turfgrass disease, weed, and insect control; turfgrass cultivar performance; fertilizer products and practices; athletic field research; compost utilization; and much more.

The ornamental component of the Penn State Turfgrass and Ornamental Field Day will feature a variety of tours and hands-on demonstrations for landscapers, nursery operators, and others interested in ornamental horticulture.

To register for this class, visit http://extension.psu.edu/events and search for event link using the keyword “turf”.

Quote Of The Week: “The reason I can’t follow the old eye-for-an-eye philosophy is that it ends up leaving everyone blind.” Martin Luther King Jr.

Leon Ressler

District Director – Chester, Lancaster, and Lebanon Counties
Penn State Cooperative Extension

Phone (717)-394-6851
Fax (717)-394-3962
lressler@psu.edu