Evening star., 1938-08-27
Trees Need
Quantities
Of Water
Vitality Increased
During Drought
BY Fertilizing.

N o1H tiec may Sutk up dIlu uls-
charge through its leaves as much
as so gallons of water on a single hot
day! It's fact. Transportation,
one Of the vital processes taking place
in all green things. literally pours
water in vapor form through the leaf
pores all summer long. Unless the
root system Is able to provide water
for this process. the leaves dry up.
and are unable to manufacture food
necessary for the growth and vitality
Of the organism.
For this reason, and because Of the
widely varying conditions in different
parts OF the country, 1t is difhcult to
give a specific answer to the thou
sands OF tree owners who ask. How
much and how often should I water
my trees9" The only real reply Is.
'As much and as often as they need
it."
As We have seen, q tree with a big
leaf surface requires more water than
one whose leaves are naturally sparse
or small. Climate is another obvious
factor. A less apparent consideration
is the grass above which the tree
grows. The wide. shallow root sys-
tenn Of heavy lawn gets "first dibs"
on surface applied moisture, and may
exhaust a large proportion of it be-
fore the tree roots have a chance.
Instances have come to our atten-
ton where it was actually impossible
to supply soil with as much water
as the combined root systems of big
tree and q thick lawn took out i'm
mediately.
The practical rule number one for
tree watering, then, Ia to wet the
ground thoroughly whenever it is dry
Breaking q few pieces Of soil in the
hand will show very quickly whether
the need exists.
Rule number two is to wet enough
ground. 1t Ia hard to realise the ex-
tent of trees root system. Since
these roots themselves need water in
order to carry on their useful lives As
suppliers of food and drink to the
rest Of the parts, care should be taken
to water q wide area. The shortest
distance for water to travel 10 down.
Sideways movement of moisture
through the soil is, contrary to gen.
eral belief, slow and limited. It is
best, therefore, to cover the whole root
system from above and to the depth
occupied by the Noots. This may re-
quire half an hours aprinkling, or it
may require half day.
The best time for tree watering is
in the evening. This gives the water
full opportunity to sink we'll into the
soil before the drying sun can reach
1t. Likewise. watering under hot sun
may have = harmful effect on grass
OF flowers.
Fertilization has been found to have
a definitely good effect on growth and
health of trees during dry years OF
seasons, when it is difficult or i'm
possible to keep soil moist. Reported
cases have shown well-fertilized trees
thriving in drought seasons, where
other uncared-for specimens gave uT
the battle and died. The beneficial
effect here Is due to increased vitality
OF the tree, and consequent rApit
growth Of the root system, which ii
this way gets larger share OF wha
moisture there is.
For these same reasons, newly
planted trees absolutely must be kept
pruned back as far as possible. Ever
with the most skilled and careful worl
in transplanting. 4 tree loses a high
percentage Of the tiny feeding root
which really bring home most Of thu
bacon. Those replanted intact hav,
all they can do to supply few strong
healthy leaves. A tree full Of them /!
too much for the roots to handle, ant
the whole tree dies. II the tree Il
properly trimmed, however, thos'
leaves remaining can thrive on tn,
diminished food and water, and . new
root system develops during the grow.
ing season following transplantine
Proper fertilization is 4 great help tx
the struggling new tree in its search
for food and development Of strong
new roots.
Because of their comparatively
quiet and inactive lives, We are ap,
to underestimate the material need!
Of trees. Remember that they get hun
cry and thirsty as We do, and that ex-
cept In unusual cases. you should keer
the soil In which they live moist ane
rich.