From caseyo at cc.usu.edu  Tue Jan 25 04:33:23 2005
From: caseyo at cc.usu.edu (caseyo@cc.usu.edu)
Date: Tue Jan 25 04:33:29 2005
Subject: air pollution, leaf necrosis coorelation?
Message-ID: <1106266163.108249.265650@c13g2000cwb.googlegroups.com>

OK, here's another one, I live in the place witht the dirtiest air in
the country(logan, utah) our greenhouse is experiencing some foliage
issues( Tip necrosis in salix nigra, and localized needle wilt in some
austrian pine) could air be a likely cause?

From caseyo at cc.usu.edu  Tue Jan 25 04:33:25 2005
From: caseyo at cc.usu.edu (caseyo@cc.usu.edu)
Date: Tue Jan 25 04:33:39 2005
Subject: salix nigra tip necrosis
Message-ID: <1106264308.337401.224330@f14g2000cwb.googlegroups.com>

Hi,
our population of black willow unanimously decided to get small brown
spots on the leaves and tip necrosis on the upper leaves, there are non
insects involved (it is a laboratory greenhouse)
The avreage daily temp is 21 C, and the photoperiod is a constant 14
hours. Any Idea what could be the cause? very well watered,(perhaps too
well?)