Get your Waterhemp Populations Screened for Herbicide Resistance

By Mark Loux, OSU Extension

We have been screening a random sample of waterhemp populations for herbicide resistance over the past two years.  Herbicides used on the screen include mesotrione, atrazine, 2,4-D, fomesafen, and metolachlor.  Results of our research show that it’s possible for Ohio waterhemp populations to have some level of resistance to one, several, or all of these herbicides.  Glyphosate is not included because we assume almost all populations are already resistant to this.  We are also part of a regional project that has been screening for dicamba and glufosinate resistance with populations that we supply, although none has been identified to date. Continue reading

Scout now for cressleaf groundsel in hayfields, or pay the price in May

Cressleaf GroundselBy Mark Sulc, OSU

Some hay producers have been unpleasantly surprised in the past when cressleaf groundsel infestations became evident in their hay fields in May prior to first cutting.  Cressleaf groundsel in hay or silage is toxic to animals, and infested areas of the field should not be harvested and fed.  Groundsel is a winter annual, emerging in late summer into fall when it develops into a rosette that overwinters.  Growth restarts in spring, with stem elongation and an eventual height of up to several feet tall.  The weed becomes evident in hayfields when it becomes taller than the alfalfa/grass and develops bright yellow flowers in May.  The problem with passively waiting until this point to discover that the hay is infested with groundsel is that: 1) it’s too late to control it with herbicides; and 2) hay from infested areas has to be discarded instead of sold or fed, and large plant skeletons are still toxic even if herbicides were effective on them.  Groundsel plants finish their life cycle in late spring, once they flower and go to seed, so it should not be a problem in subsequent cuttings. Continue reading

Late-Season Waterhemp – The Goal is Stopping Seed

Flowering Waterhemp

By Mark Loux OSU Extension

In our windshield scouting of soybeans this year we have seen a lot of weed-free fields.  This makes sense given the shift toward Xtend, LibertyLink, LLGT27, and Enlist soybeans over the past several years, which provides us with effective POST options for our major weed problems – common and giant ragweed, marestail, and waterhemp (now if we could just get rid of the baggage some of these traits carry).  We are however getting many reports of late-season waterhemp as it grows through the soybeans and becomes evident.  This also makes sense given that statewide we are in the midst of an overall increase in waterhemp, and continue to move up the curve in terms of the number of fields infested and the size of the infestations.  Prevention and management of waterhemp and Palmer amaranth has been one of the primary goals of our state and county educational programs for half a decade or more.  And one of the most important points about waterhemp and Palmer that we try to get across is their capacity for prodigious seed production – 500,000 to upwards of a million seeds per plant – and what this means for their ability to rapidly ramp up populations, infest equipment, etc. Continue reading

Paulding County Fertilizer and Pesticide Re-certification to be offered January 29

The OSU Extension Office in Paulding County will be hosting the Fertilizer and Pesticide Recertification on Tuesday, January 29, 2019.  Cost of the classes are as follows:

  1. Fertilizer Re-certification $10.
  2. Pesticide Re-certification $30.
  3. Registrations received after January 23rd will receive a $10 late fee.

Fertilizer re-certification will be held starting at 8:00 AM.  Please arrive between 7:45 and 8:00 AM to check in. Pesticide recertification registration will begin at 9:00 AM.  The class will begin at 9:15 AM.  Please call 419-399-8225 to register or email noggle.17@osu.edu.  Eventually online registration will be open with the option to pay by credit or debit card.  Payments can be made in person or by mailing a check to Paulding County Extension, 503 Fairground Drive, Paulding, OH 45879