, and he has been kind
enough to enumerate the following conditions under which leaf disease is
liable to occur in the cases of good soils under good shade:

"In the case of good soils under good shade trees," writes Mr. Graham
Anderson, "leaf disease is liable to occur under the following
circumstances, or at the following times:

"1. From the soil being saturated at some critical period of growth,
particularly just when secondary growth commences in September.

"2. During the time when the plants are maturing a heavy crop.

"3. After the plants have been exhausted by ripening a heavy crop.

"4. After heavy weeds--particularly if late in the season.

"5. After a heavy digging where roots have been cut.

"6. After pruning without manure having been applied, or from want of
digging.[57]

"7. Even after manuring when the trees have large succulent roots in an
immature condition--generally a sign that fibrous surface roots are
deficient, and that large, deep-feeding roots are present in excess.

"8. After large quantities of green or rotting weeds have been deeply
buried, or large quantities of acid, unrotted, or forcing manures have
been applied.

"Leaf disease is also liable to occur:

"1. In poor gravelly soils, and on land which has caked in the hot
weather, or become unmanageable during rain.

"2. On land where ill-balanced manurial preparations have been used.

"3. In soils suffering from a deficiency of the available supply of
phosphates and alkalies.

"4. Under unsuitable shade trees."

Now it is to be observed that these are preventable causes, or
aggravations of leaf disease, and, if carefully attended to, the planter
will have little to apprehend from leaf disease. Mr. Anderson, in his
communication to me, lays, and very rightly, particular stress on the
maintenance of the physical condition of the land and its state of
fertility. And it is satisfactory to find that he is exactly confirmed by
Mr. H. Marshall Ward in his third report (dated 1881) on coffee leaf
disease in Ceylon, and he points out (p. 3) that "Leaf disease appears to
affect different estates in different degrees on account of varieties in
soil, climate, and other physical peculiarities."

"But," he continues, "I would draw particular attention to this. Careful
cultivation and natural advantages of soil, climate, etc., enable certain
estates to stand forth prominently, as though leaf disease did not affect
them, or only to a sli