Last year's experiment of wrapping copper screen on young blighted tree's fungal cankers has apparently saved a heavily cankered Bartlett and Summer Crisp pear, while our affected Luscious pear and a Rainier cherry (both challenges to our zone) treated likewise succumbed to several uncharacteristic -30� days over the winter. An un-cankered Black Tartarian cherry also croaked from the cold; unaffected North Star and Montmorency are doing fine without the wraps.

I have recently applied the wraps to a blighted Compass Cherry plum on the lingering cankers, as well as a Butternut (white walnut Juglans cinerea) that has struggled since we reintroduced it to the north woods of Wisconsin in 2011. I must say that it seems to be succeeding, particularly with the Juglans, which was on the ropes.

As the dose is unmeasured and continuing, any advice on if and when the copper need be removed would be most appreciated.

for photo of Butternut with copper wrap over canker:
http://twodogsgonewild.blogspot.com/...or-dogdom.html
fruit tree wraps also depicted in previous posts there
For description of Butternut malady:
http://www.na.fs.fed.us/spfo/pubs/ho...but/ht_but.htm