6 
Colorado Experiment Station. 
a great deal of data on this point which will be presented by him in 
due time. The money loss to the farmers in seed alone has amounted 
to thousands of dollars. But the orchardist has been unquestionably 
the heaviest loser, for not only has he been deprived of the crop for 
the current season, but he has also lost the trees upon which he is 
dependent for future crops, at least we have yet to see a single tree 
which has shown any indication of recovery. Added to this and 
worse than all, perhaps, is the utter worthless and hopeless condition 
of his soil for agricultural purposes. The apple, cherry, apricot and 
plum, all appear to suffer about equally, while the pear and peach, 
thus far, have exhibited marked resistance, the peach having been 
observed to suffer least of all. 
The symptoms of excessive nitre in the soil as manifested in apple 
trees are so characteristic that it may be well to describe them briefly 
in passing. The first indication is the firing or burning of the leaves 
along the margins, beginning at the apex, extending rapidly along the 
edge, inward toward the midrib and downward toward the base until 
the entire leaf has turned brown. There is no occasion for anyone 
who is familiar with the yellowing of foliage due to lack of proper 
drainage to confuse this with the nitre burning, for the appearance of 
the leaves in the two cases is entirely distinct. Whole trees have been 
known to undergo this transformation in less than three weeks time. 
In fact, Dr. Headden reports having killed a four-year-old tree in an 
experimental orchard in four days by applying twenty pounds of ni¬ 
trate of soda around the roots and then irrigating at once to bring the 
nitre into solution. In reference to the behavior of this tree, he says, 
“The effects were in all respects similar to those produced in other 
orchards” under natural conditions. If the burning of the leaves oc¬ 
curs early in the season, the trees will often exert a feeble effort to 
put forth a second crop of leaves. These are usually small, whitish 
leaves and inclined to be rather pubescent. Such trees, laden with 
one-third to one-half grown apples, seldom mature any fruit, and in 
all probability will be dead by spring. If the attack comes late in 
August or September, the chances are that the fruit will mature, but 
it will be undersized and of poor quality; no new leaves will be ex¬ 
pected to appear and the old ones will cling to the twigs late into the 
fall. The following spring, it is very likely that an attempt will be 
made at leafing out, but as stated above the leaves will be small, yel¬ 
lowish-white and few in number, and by the middle of the season the 
tree will be dead. 
Before proceeding further, I wish to make it perfectly clear that 
what I have said is not to be interpreted as applying to all of our 
arable land or to more than a very small percentage. While the mat¬ 
ter is eminently serious, it by no means justifies the position that our 
agricultural interests as a whole are in jeopardy. Just how we shall 
meet these difficulties, and correct the trouble, we are not prepared to 
say at present, but we are hopeful. As our knowledge of the subject 
grows, we feel confident that remedial measures will be forthcoming 
