Powdery mildew has been difficult to manage and can lead to low yields if it gets out of hand. Like downy mildew, powdery mildew starts out in or near the ground, but powdery mildew works its way from the bottom to the top of the bines very quickly, while downy mildew normally stays around the crown. All of our yards are checked at least once a week by professionals as well as by us when we drive around daily.
Burn-Back and stripping are one of the best ways to help control and defend against major powdery mildew outbreaks.
Sadly I do have a few pictures of powdery mildew:
Powdery Mildew spot on a leaf found about five feet from the ground. This is something we would rather not see in our yards.
Close up of burn-back in a high alpha hop yard, notice the foliage browning from the ground to about four feet up.
View down row of super high alpha's that have recently been burnt back.
Links to more information on Powdery Mildew:
Oregon State University -Plant Disease Control:
http://plant-disease.ippc.orst.edu/disease.cfm?RecordID=603
University of Idaho - Plant Soil Entomological Sciences:
http://www.ag.uidaho.edu/PSES/Research/r_ent_hoppest_powderymildew.htm
4 comments:
Great information that you provide.
Could you expand on what you mean by 'burn back'? Do you actually use fire? How is it performed?
Keep up the good work,
Thanks
Matt
Burn-back can be done with either herbicides or actual flames. We no longer use fire like we did in the past as fuel costs are very high, so we handstrip our worst yards and use herbicides on the other yards to control mildew.
Tyler
What is the active ingredient in the herbicides you use?
TD
The Pacific Northwest Weed Management Book contains much of the information needed including the active ingredients on commonly used herbicides for burn back in hops. See section toward the bottom headed "Green Sucker Suppression in Hops" i.e. burn back.
http://pnwpest.org/pnw/weeds
Select the Chapter: Legumes, Winter Oats, Rape Seed, Corn, Hops
Then select the Section: HOPS
Tyler
Post a Comment