BEN # 37

Adolf Ceska aceska at CUE.BC.CA
Wed Aug 26 08:59:00 EST 1992

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No. 37                            August 26, 1992

Address: aceska at         Victoria, B.C.

From: George Douglas

Recently, Steve Darbyshire (Agriculture Canada, Ottawa) sent me
a xerox copy of a B.C. collection of Trisetum wolfii Vasey. 
This is a first record for B.C. and, according to the maps in
Flora of Alberta (Packer 1983) and the Rare Plants of
Saskatchewan (Maher et al. 1979), is a fourth record for Canada.
The B.C. collection was taken in 1968 by George Scotter (CWS) in
the alpine zone (2690 m) in Mt. Assiniboine Provincial Park.  It
is quite likely that other B.C. collections of this awnless
Trisetum are hidden in various collections.  The species is
relatively frequent in the western U.S. from E WA and MT south
to NM and CA.

From: Meindert de Jong <VLINDERS at RCL.WAU.NL>

Chondrostereum purpureum is a commonly occurring fungus which
will probably be developed as a biological silvicide to con-
trol stump sprouting in hardwoods. It is a wound invader of
broad-leaved trees. Common presence of this Basidiomycete in
nature causes a natural infection danger. The intended biocon-
trol may cause an added risk to non-target plants besides the
already occurring natural risk. To estimate the natural infec-
tion pressure, I want to perform a survey of the natural
occurrence of basidiocarps of this fungus in the woods nearby

Accordingly, I would like to inspect some one year old stubs of
deciduous trees, when I visit Victoria (in September?). If you
happen to know some one year old clearcuts of deciduous forests
(especially with Populus spp.), botanical gardens with much
pruning of broad-leaved trees, stumps of felled roadside trees
in the surrounding of Victoria, then I would greatly appreciate
to know the exact location!


I came across an interesting posting in BIOSPH-L on a possible
conflict between the protection of monarch butterfly and listing
milkweed as a noxious weed. I solicited answers from Roy Cranston,
weed specialist, and from Cris Guppy, entomologist. - AC


The Monarch butterflies winter in a very small area of Mexican
forest, which is in danger from illegal logging and intrusion by
squatters.  In the past few weeks the Mexican government has
made steps to extend the Monarch butterfly's land reserves.

Canada is also being urged to re-think it's classification of
the Milkweed as a noxious weed.  The milkweed is an essential
plant to the Monarch Butterflies survival.  The current act
requires land owners to destroy all milkweed they encounter.

Roy Cranston, weed specialist:

Milkweed is not listed as noxious in the Seeds Act and
Regulations administered by Agriculture Canada nor is it
considered noxious under Weed Act legislation in British
Columbia or Alberta. According to Bhowmik and Bandeen, Can.
Journal of Plant Science, Biology of Canadian Weeds Series, July
1976, milkweed is classified noxious in Ontario, Manitoba,
Quebec and Nova Scotia.

I don't know what the situation is in other provinces.

Cris Guppy, entomologist:

Monarchs breed in southern BC, with the larvae eating milkweed.
However, even if all milkweed was eliminated from the province,
I do not think that the overall Monarch population would be
greatly affected because too few adults are produced in BC. The
Monarch population west of the Rockies overwinters in California
and Baja.

The Monarch population east of the Rockies overwinters in
northeastern Mexico, and is the one which overwinters in the
threatened forests mentioned in your memo. There were newspaper
reports of a very severe (30%?) die off of overwintering
Monarchs this past winter, apparently due to logging of the
forests exposing the butterflies to winter storms and freezing.

The eco-tourism idea has proven to have a significant protective
value for the overwintering Monarchs, because the dollar value
to the local villages is much higher than that received from
logging. Eco-tourism has only been developed for a couple
overwintering sites however.

Monarch breeding in southern Canada east of the Rockies probably
results in a highly significant contribution to the
overwintering population. Hence reduction in the amount of
milkweed available for use as a larval food plant is likely to
result in a significant reduction in the size of the
overwintering Monarch population, which is likely to make
overwintering deaths much more significant. Ontario and Manitoba
have the largest breeding populations of Monarchs, so their
designation of milkweed as a noxious weed is especially
significant, but some breeding occurs in every province that has

As an added note, milkweed is a very significant source of
nectar for many species of butterflies and moths, as well as
wild bees and other insects. It is recommended as a nectar
source in all books on butterfly gardening.

Milkweed is also the only larval food source for a number of
insects, so if milkweed becomes rare in a province, the insects
are likely to become endangered in that province.

From: Art Guppy

I hear that the new version of Jepson's Manual of the Flowering
Plants of California will be published this year. Has anyone any
information on this? Title? Publisher? Price?

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