Hemp Post #14


Reproductive Stage has Begun:

On a few farms this week, the flowers have begun to form on the earliest varieties.  Sadly, we have also sighted some males in the CBD crop.  Males will usually develop before females so that pollen is available throughout flower maturity.  Now is surely the time to start scouting for males closely, looking for the tell-tale pollen sacks at the juncture of the plant and to rogue out any volunteer plants that have grown from last year’s dropped seed.  See photo of male here taken by Johanna Gertin, Intern.  Note the round pollen sacks.    

Please review the Hemp Update from 5/31 for great pictures of males vs. females.  I do not expect any females to have become hermaphrodites as of yet since flowering has just begin,  That transformation is normally the result of a long time flowering without pollination. 

Leaf Spots

Different leaf spots have been sighted.  If you see spots that you believe are disease, please contact your specialist for diagnostic information.  We may be able to identify with the picture alone or we may need to send samples to Cornell for pathology.  Even if we know what it is, Cornell might like a sample for comparison to other diseases we have collected on hemp.  The newness of this crop makes this kind of collection critical for future production.

Herbicide Residue?

These past 2 weeks Johanna, the Intern, and growers have been noticing unusual yellowing and or burning of leaves.  The yellowing was not from nutrient deficiency as the patterns were not what one would see with lack of nitrogen or other nutrient.  Usually, nutrient deficiencies occur on oldest or youngest leaves (depending on the nutrient) and this was occurring equally on all-aged leaves.  Similarly, we saw burning of leaf edges that resulted in curling.  In both cases, the problem led back to herbicide reside from pre-plant applications.  Because the past couple of weeks have been hot and dry we think it was sort of a “perfect storm” of stress to the plant and its roots.  If you, too, see inexplicable discolorations be sure to contact your specialist to get a diagnosis.  It is important that we continue to develop a list of herbicides that hemp may be sensitive to for future applications. 

US Senate Ag Committee Hearings (held last week) on Hemp Production can be seen here:

https://www.agriculture.senate.gov/hearings/hemp-production-and-the-2018-farm-bill

Meeting Reminders:

Cornell Help Field Day in Geneva 8/13/19:

Hudson Valley Hemp Meetings  (2 locations) 8/15/19:

https://interland3.donorperfect.net/weblink/weblink.aspx?name=E190538&id=507

Did You Miss One?  Past Updates Here:

https://s3.amazonaws.com/assets.cce.cornell.edu/attachments/39446/HempUpdate_13.pdf?1564428265