THE NATIONAL NURSERYMAN 
273 
The White Pme Blister Rust Quarantine 
Read at the Milwaukee Convention by Prof. F. L. Washburn 
T 1IE few remarks, which I have to make are in no 
way to he considered as a criticism upon the ac¬ 
tion of the Federal Horticultural Board in its 
connection with the White Pine Blister Bust. The 
Board has been placed in a trying position and lias evi¬ 
dently acted wisely and with foresight in its effort to 
protect the great pine growing region of the far west. 
The biology of this rust disease is probably known to 
most of you, and you are aware of the fact that it spreads 
from live leaf pines to currants and gooseberries, upon 
which it is found during the summer in two stages, the 
last stage sending spores to pines. It may travel many 
miles upon currants and gooseberries, particularly upon 
the black currant, for which it has a special affinity. 
While this disease will not ordinarily kill a large white 
pine, it will destroy young trees and hence it is a menace 
to reforestration in the United States. 
Originating in Europe, the infestation in America can 
be traced to importations before severe restrictions were 
put upon importations. The raising of eastern white 
pine, has on account of this disease been practically pre¬ 
vented in England, Holland and in Denmark. It has 
been known to exist for several years in some of the 
eastern states, principally New York, Vermont, New 
Hampshire, Massachusetts, Pennsylvania and some 
others. 
It is of existing conditions of which I would like to 
speak, reminding you that a paper offers only a skeleton 
upon which to hang a discussion; the discussion being 
much more valuable than the facts outlined in a formal 
paper. If I, therefore, bring to your notice certain con¬ 
ditions, in Minnesota for example, I believe that by so 
doing I will illustrate conditions which exist in other 
states, particularly Wisconsin and Michigan. 
To be explicit, we have found in Minnesota only two 
infestations, both of them east of the Mississippi River 
near the Wisconsin border, and one of them known to 
have been caused thru a shipment of pines from Ger¬ 
many, coming thru an Illinois nurseryman to a party in 
Wisconsin close to our eastern border. Some of these 
pines were brought across the St. Croix River into our 
state by a nurseryman and in that nursery the disease 
was first discovered. In another nursery, 40 or more 
miles to the south, a second infestation was discovered 
by the Minnesota Inspection service upon a pine standing 
in a row of trees, which had been in the ground in this 
nursery for fourteen years or over. This was found on 
the main trunk. The source of this infestation we are 
not sure of, and it is now a matter of investigation. A 
second infestation in this same row was discovered later. 
It can hardly be charged to the negligence of any 
officials or scientific men that the white pine blister rust 
has obtained a foothold in any state. Critics might say 
that the State Nursery Inspectors in the states affected 
were guilty of negligence, and that the Plant Pathology 
Divisions of the various experiment stations should have 
become cognizant of the presence of this disease at its 
very first appearance. We do not believe, (we speak 
particularly of the two stales in the northern Mississippi 
Valley, namely:—Wisconsin and Minnesota), that either 
of these departments arc guilty of oversight under the 
present circumstances. 
In Minnesota the Inspection Department has been 
watching lor several yeais, shipments of pines from 
Europe to Minnesota Nurseries with negative results, not 
dreaming that we would receive the infestation from* our 
sister state, Wisconsin. 
Our Inspection force has carefully combed all nur¬ 
series in the state raising five leaf pines, and so far we 
have 1 ailed to find it outside of the localities mentioned. 
In this work the Plant Pathology Division of the Ex¬ 
periment Station is co-operating in an advisory capacity, 
and we are also assisted in this work by the State For¬ 
estry Service. All Minnesota nurserymen appear will¬ 
ing to co-operate and have shown their willingness in at 
least two instances in a very practical way. It is a 
significant fact, and a very important one from the stand¬ 
point of the nurseryman, that so far, with the exception, 
1 believe, of one not well authenticated instance, it has 
been lound impossible to carry tins disease thru a winter 
on dormant currants and gooseberries. It is also to be 
noted that the Federal Board places no restrictions upon 
the importation of Bibes from Europe. 
In the interest of nurserymen, therefore, and if the 
speaker is at all critical it is upon this point 1 wish to 
emphasize the following facts: 
Allho this disease has been known to exist in various 
eastern states for several years, no restrictions whatever 
were placed by the Federal Board upon these states. 
In other words, these states have been at liberty to ship 
into Minnesota, Wisconsin, and Michigan, (I mention 
these states on account of the White Pine industry here), 
white pines and other five leaf pines without limit. The 
three states above mentioned have not been protected 
from infestation. At the same time, last spring, but 
evidently too late to have a bearing on last spring’s ship¬ 
ments, nurserymen in Minnesota, also probably in Wis¬ 
consin, the Dakotas, and Iowa received requests from 
the Federal Board not to ship white pines, currants or 
gooseberries west of the Dakotas, and west of a line 
drawn south from there. This directly affects the 
trade in eastern Montana, which territory is being ra¬ 
pidly settled, and sending out big demands for such fruits 
as currants and gooseberries. The fact, as above stated, 
that, apparently the disease does not go over on dormant 
currants or gooseberries would appear to make this re¬ 
quest deserving of reconsideration. 
It is this feature of the quarantine that I should like 
to see discussed by the nurserymen as well as the sub- 
