Missouri Valley times., 1901-11-14
SIRAlGHT5~ClGAF
How to Study Autumn
Leaves.

How to Study Autumn
Leaves.
The governments new Burea,
OF Plant 1ndustry is taking III
the problem of how our gorgeous
autumnal foliage receives its var.
|iegated coloring. Tint is one OBJ
Iject of the Investigations which
are now being made by Albert L
Woods, lately appointed patholo'
gist and Psychologist of the bu.
reau.
| 10 preserve autumn leaves Mr.
Woods says the gatherer should
Immediately lay them flat between
two sheets of new blotting paper
spread upon a table top and COW
cred by stack of heavy books. 1t
is essential that all moisture
should be pressed out Of them.
BY this simple process they should
be dry within three or four hours.
So treated they will retain their
beautiful color for years, provided
they are not exposed to the direct
light of the sun. If not thorough
ly deprived OF their normally
large percentage of water they
will soon assume a dirty brown
tint.
The color of leaf, said Mr.
Woods, in explaining his investi-
cations, is furnished by minute
grains Of pigment within it's coils.
What we see in the fresh leaf is
not simple green, but combina-
tion OF many pigments, which,
when mixed, appear as solid
green.
Red is oneof the color elements
Of fresh leaves. Reddish coloring
matter is usually in liquid form,
within the sap contained by the
leaf cells. Yellow, another nor
NAL color element, when combin-
ed with green, is the natural shade
of the grains of pigment within
each cell. Brown is the normal
color of the wallis of the cell.
TO explain the leaf cell, Mr.
Woods says that he would exhibit
a very thin rubber ball filled with
the white of an egg mixed with
water. He would add to this liq-
uid sufficient red dny to dissolve
aud color the entire solution. He
would add also Paris green, whose
minute grains will not dissolve
Yellow grains of some powdered
substance, likewise insoluble, he
would mlnele with the green. The
rubber ball itself would be brown,
corresponding to the normal color
of the leaf cells wallis Holding
the ball up to the light, the COM
bination of the colors in its tex
ture and interior substance would
be the green tint of tina plant life
10 demonstrate the antumnal
changes in leaf tints he would
spread upon table hundreds of
green bends, interspersed with
others of brown, yellow, and red. !.
Then he would take out all of one
color then all of another, and so
on, the general shade or tint of
the entire mass undergoing a
change all the while. Just so in
the autumn leaf-whcn any of its
elementary colors disappear the
general effect Of those remaining
clustered in any particular area
is altered.
LIE an autumn leaf turns eatire-
ly red this tinting ls due to the
fact that only its red pigment is
left. Ii it is yellow all of the other
coloring has been destroyed, ex-
cept the minute yellow grains. If
the leaf turns Drawn it can be
safely diagnosed as dead. All
living tints have disappeared,
leaving only the brown walls of
the cells. The brown leaf is a
dingy ruin, within which every
spark of lise has been extinguish-
ed.
"Ihere has long been contro-
versy as to the cause of the
autumn leafs distoloration," said
Mr. Woods. "Some botanists have
attributed it to frosts. We are
finding that light frosts, not suf1i-