Colorado Experiment Station 
36 
The bleeding is sometimes quite profuse, so much so that the outflow¬ 
ing sap may encrust the trunk with a yellowish white deposit for 
several inches below the split, or if on a limb for a foot or more. I 
have seen it drip and build little stalactites three inches or more in 
length and cover the limb with a deposit an eighth of an inch thick. 
This material seems to be gathered from the soil and is the 
sap or solution sent up into the tree by the roots and 1 is probably not 
produced within the limbs or tissues of the tree. This of course 
cannot be observed, but the following example will make my meaning 
plain. A limb of a Jonathan apple tree was cut off on the eighth of 
April. It was cut off close to the trunk of the tree, not more than 
two feet from the 'ground. The tree was not healthy, but no more 
unhealthy than the average tree in the orchard. On the twelfth of 
May I found that this wound was bleeding and was already covered 
with the deposit described above. This sap was then exuding through 
the medulla, as was easily observable. No bleeding could be observed 
from the sap wood. This bleeding is very marked in some orchards 
and practically absent in many. The deposit is the same in appear¬ 
ance wherever I have seen it. The soil of these orchards is under¬ 
laid bv marl and the soil itself is marly. I think that the great ma- 
jority of our soils carry more than five per cent, of carbonate of lime. 
This deposit contains 25.00 per cent, of calcic oxid and 49.0 parts 
per million of arsenic, calculated as arsenic acid. The cracking open of 
the bark and the bleeding is shown in Plate 5, p. 16 of Bulletin 131, 
and as it is still representative we will use it again as Plates VII and 
VIII. 
I know nothing about the contents of total solids in normal apple 
tree sap, but this sap is eviolently very rich in total solids which 
as represented by these deposits are soluble in cold and hot water, 
but difficultly soluble in alcohol. If to the aqueous solution some 
alcohol, not enough to precipitate it, be added, fine acicular crystals de¬ 
posit on standing. Calcium is essentially the only inorganic base pres¬ 
ent but is accompanied by a small amount of magnesia and the alkalis 
potassium and sodium. 
Lime was not mentioned in the preceding section because it is 
always present to some extent in the ash of plants and in all soils, 
and the amount of lime added with the arsenite of lime is extremely 
small when compared with the lime in our soils for which an estimate 
of 65 tons per acre foot is very moderate. The soil of one of the 
orchards referred to carries in the surface foot calcic carbonate equiv¬ 
alent to 224 tons of burnt lime, while the subsoil is still more limey. 
The supply of lime is excessive, the ability of plant roots to dissolve 
calcic carbonate is well known, so the appearance of lime in these de¬ 
posits is no matter for surprise, but the annearance of so large an 
amount of arsenic, 49 parts per million, is sufficient to raise a question 
in regard to its source and its relation to the lime. 
Some plants are calcifugous but the apple does not seem to 
belong to this class, for it does well and lives long in limestone soils, 
not only m other states but also in Colorado. I know of a small or- 
