Evening star., 1941-11-15

lively new product produced by the
Fibre Products Division, Corning
Glass Works, Coming, N. Y. A
thickness of two inches of glass wool
seemed to give pest results. and
plants wintered under this covering
better than under any OF the other
materials used. There was cOnsld-
cradle evidence that the light trans
mitted BY the glass wool was OF de-
cided value, especially upon plants
which keep their leaves through the
winter The plants retained their
green color and there were no dead
or rotting leaves. Results were
especially good on large plants OF
foXgloVe and Canterbury bells.
Snow was found to be a good COW
ering. In regions where snow is on
the ground all during the winter,
this is Of interest, although OF
course in most sections this infor-
nation IS of little value because
falls OF snow come and 90 and hence
do not answer the true purpose Of
a mulch-that of preventing alter
nate thawing and freezing and con-
sequent heaying of the plants. In
these experiments. the snow acted
as a good insulatOr and decreased
f1uctatlon in temperature. Re
moval Of the snow from check plots
resulted in much winter injury.
Oats straw gave good result. Oats
straw gave better results than other
straw mulches. This mulch was ap-
piled TO a depth OF inches. One
drawback, however. is that cats
straw is apt 10 contain a gIea-
many weed SEEDS.
Excelsior gave very poor results
Mulch was applied 10 a depth Of
inches. Did not give sufficient in
sulation TO prevent temperature
fluctuations. There was this IN its
favor, hoWeyer-it did not become
wet or Soggy.
Manure gave results about equal
to excelsior. A 4-lnch mulch was ap-
piled. Ii permitted some fuctatlon
in soil temperature. Another draw
back was that great deal OF moIS-
ture was retained around the plants,
and the soil renamed wet through
out the winter. In some plants this
would induce rettlng.
Leaves were not satisfactory. Mulch
of six inches was applied. Show eG
very excellent insulating value arG
prevented fiuctuatlOn N tempera-
ture. but even 50. their effect was very
detrimental 10 the plants. because
moisture seemed to cOndense on the
lower layer OF leaves, resulting in
sOggy condition.
Balsam wool Il thickness, showed
very poor insulating value compared
to other mulches: being backed by
black waterproof paper, it was COM
pletely impervious TO light and
moisture, and the soil was very wet,
Nearly 1907 Of the plants died,
Burlap IL thickness. had little III
sulating value, and the ground
tended 10 freeze and thaw much the
same as though no mulch were on
it. Heaying was a little less than
without a mulch. Burlap proved OF
little value as a mulch.
Peat moss. applied at a thickness
of three inches, proved to be very ef-
fective in preventing fluctuations in
temperature and with some plants
decreased winter killing. With such
plants as foXglove and Canterbury
bells, however, it was somewhat
detrimental,
Advantages of glass wool over other
materials:
The chief advantage of glass wool
over other materials, as mulch,
are:
|. It's complete sterility; absolutely
free of all disease, insects and
weed pests.
2. 1t is excellent insulating mate
rial. and therefore prevents vio-
lent fluctuatlon in soil tempera-
ture.
3. It lets through little light,
which is very great advantage
for evergreen plants. particularly
the group of Alpine plants nor
mally grown IN rock gardens.
4. 1t permits good aeration and thus
prevents smothering or suffOca-
ton of the plants.
5. 1t is indestructible and can be
used for several years.
The only disadvantage it appears
to have is a slight difficulty in hold
ing it on the beds. This can be
overcome simply by placing some
course chicken wire on top of it, and
pinning the chicken wire down.
Points to remember before mulch
ing:
Before mulching perennial beds OF
borders, clean up and burn all old
foliage, to prevent wintering over OF
disease
Never mulch until the ground Is
| well frozen, in order to avoid nesting
of field mice in the mulch and in
| jury to plants from these mice.
Points to remember when remov-
ing mulch in spring:
Watch for plants which may have
been heaved up and left with their
roots exposed. See that these are
again placed at the proper depth in
| tho coil