Omaha daily bee. (Omaha [Neb.]) 187?-1922, 1911-05-10
European Disease
Threatens White Pine
Blister Rust, Imported with Nursery
Stock, Endangers the Reforesta-
ton Projects.

The dangerous European disease Of white
pine (Cronartium ribicola), which was re-
Gently introduced into America, was by
the prompt and active cooperation OF all
parties concerned eradicated. as far as
found; but there is no evidence that all
the cases have been found, nor is there
any means of pre-, euting the importation
of more diseased white pine nursery stock.
The reforestation movement has created
a market for a considerable amount of
white pine stock and the producing ca
pacity of the American nurseries has not
kept pace with the demand. The prices for
American trees are higher than European
prices for the same grade Of stock. so that
while white pine stock has been imported
for years for ornamental grounds, IL has
been only during the last five years that
the importations have been for reforesta-
ton. While the monetary first cost Of i'm
ported stock lie less than that of American
stock, the various items Of expense which
necessarily are incurred bring the two
nearer together than would at first be
thought, and the risks of injury from the
long trips and the danger OF importing de-
structive insects and fungus pests are 30
great that any but the most venturesome
should be deferred from importing such
stock.
There are many American nurserymen
who regularly import their 1-year-old conf
ferrous seedlings and it is safe to say that
in the spring OF 1903 100000 coniterous
seedlings were imported into this country
from European nurseries and that of these
several millions were white pine. few
foresters familiar with European condi-
tons and appreciating the danger of i'm
porting the fungus. refuse TO accept foreign
white pine seedlings and transplants.
The United States Department of Agri-
culture investigated the outbreak in 1909
Of this disease and has just issued a report
on the subject bureau of Plant Industry
Bulletin 206) in which a full and detailed
account of the fungus producing the dis
ease is given, the public is assured that
there need be no undue apprehension, as
the disease has been eradicated once and
can be again should II be imported, but
advising that America should raise it's own
white pine seedlings and that importations
from affected countries be prohibited
With the importation stopped the meth
DDS of prevention are briefly Watch the
ribes (currants and gooseberries) during
the first and second seasons; keep five
eaved pines at Least 500 feet from ribes;
remove and burn all diseased pine trees,
making inspections of the trees late in the
fall. removing diseased bushes and burn
ing them; do this annually as long as any
diseased trees or bushes are found.
The preference of this parasite (cronar-
tium ribicola) for the five-leaved pines is
of special significance to America, since
the species are naturally present through
the western, northern and northeastern
forests and are planted more OF less com
monty throughout the country, The
chances of great loss II this fugus should
even Approximate its past record In Europe
are very good. Estimates of possible
damage show that such Losses would very
soon exceed the total value OF all confer
GUS stock ever imported into the country
The United States Department OF Agri-
culture should be informed promptly and
accurately of every importation of white
pine and ribes.