Subject: forcing Rhytisma

From: [email-masked] (Kathie T. Hodge)
Date: Wed, 01 Nov 1995 12:59:57 -0300

Tar spot is all over the maple trees in my front yard.  Does anyone know
how to force Rhytisma spp. to fruit so I can look at the ascomata, or do I
have to wait for spring?

Thanks,
Kathie Hodge
[email-masked]

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From: [email-masked] (Jim Worrall)
Date: Tue, 07 Nov 1995 10:21:05 -0800

In article <[email-masked]>, [email-masked] (Kathie T.

> how to force Rhytisma spp. to fruit so I can look at the ascomata, or do I
I have used Tarspot in a spring class by collecting the downed
leaves in winter, soaking them in a stream of water, and incubating
them in petri dishes on a moist paper towel near a window.  I think
it took about a week or two.  Only about 5-10% opened nicely, but
those were worth it.

I can't tell you exactly what month it was, except it was after
February and it was still frozen outside.  I suspect the
ascomata mature during late fall and early spring.  I doubt you
could force them this early, but who knows.  If I do it
again I will try alternating them between a refrigerator and
a window shelf during incubation.

Jim Worrall

-- 
Jim Worrall
SUNY College of Environmental Science & Forestry
Syracuse NY 13210