Leland Cypress Blight Help
Posted: October 5th, 2020, 12:40 pm
We have a new property and have quite a few leyland cypress trees. The former owner briefly mentioned "they had some fungus" last year that he had sprayed. I didn't see signs of this until early September. I have been treating with manecozb every 8-10 days (depending on the rain - 3 treatments so far) since that time. I have a few questions as most of what I can find online is just copied and pasted over and over (mostly from the state ag extensions)
photos-- https://Broken image.com/a/AH2O9C5
Our weather is getting cooler - occasional 40s at night. Above average rainfall for the area in the last 2 months
I'm in Zone 7
I know - many of these are planted way too close together
No irrigation around the trees
Summer was not overly dry - should not be drought stressed
There is a creekbed behind the trees - it is dry 95% of the time and only flows after days of heavy rain
The original resource I was looking at noted manecozb is curative. Apparently it is actually preventative only. Hence, the involved areas seem to be worsening quickly. I bought a quart of thiophanate-methyl and plan to apply with my powered tank sprayer asap. Is it too late to worry about it with cooler weather coming? First frost is still a month or so away on average.
If I apply thiophanate-methyl, I am assuming I should not see any new areas of browning (but still see needles dropping in the already infected areas)
Obviously I'm going to have some large bare areas once this is all said and done. Will new needles appear in those areas? On some of the more symptomatic trees, should I count my losses and replace the tree (with a different species)?
photos-- https://Broken image.com/a/AH2O9C5
Our weather is getting cooler - occasional 40s at night. Above average rainfall for the area in the last 2 months
I'm in Zone 7
I know - many of these are planted way too close together
No irrigation around the trees
Summer was not overly dry - should not be drought stressed
There is a creekbed behind the trees - it is dry 95% of the time and only flows after days of heavy rain
The original resource I was looking at noted manecozb is curative. Apparently it is actually preventative only. Hence, the involved areas seem to be worsening quickly. I bought a quart of thiophanate-methyl and plan to apply with my powered tank sprayer asap. Is it too late to worry about it with cooler weather coming? First frost is still a month or so away on average.
If I apply thiophanate-methyl, I am assuming I should not see any new areas of browning (but still see needles dropping in the already infected areas)
Obviously I'm going to have some large bare areas once this is all said and done. Will new needles appear in those areas? On some of the more symptomatic trees, should I count my losses and replace the tree (with a different species)?