The pioneer express. [volume] (Pembina, Dakota [N.D.]) 1883-1928, 1897-09-17


a6scts tho head varisti0 especially.
when grown under glass. The Grand
Rapids variety seems to suffer least.
Too high Temperature. especially Ct
night, d conducive to the rot. Thor
ough ventilation ana care In Watering
are the remedies suggested. Other dis
eases Of lettuc6 are leaf blight, Leaf
perforation and downy mildsw. EXPO
rienoe at the station ana elsewhere has
concentrated that when lettuce u
Watsred BY sub-irrigation It 10 much
less liable to these diseases than when
surface watered. Another class Of dis
eases. affecting moro especially roses.
tomatoes. begonias. cucumbers and
some other plants 10 caused by small
eel-worms or nematodes, microscopic
In size. which work in the roots OF the
plants, causing minute engagements
or gals. The symptoms Of attack are
stunted growth, yellowing and drop
ping Of leaves, especially dying OF the
leaves at the point Of lateral margins.
with scalded aspect. in roses, which
are the most liable Of all plants to
nematode attack, the disease Is often
called "the yellows." Thorough steam
ing Of the soil before planting ID the
most promising remedy yet discovered
at the station.
The powdery mildew Of composite
plants has been successfully combated
upon cinerarias, when taken in time.
by spraying with weak solution OF po-
tassium sulphid or copper sulphate.
Probably the downy mildew Of the GU
cumber would yield to the same treat
ment. The sudden whiting Of outdoor
cucumbers is due to bacterial disease.
which may be carried from plant to
plant by the cucumber beetle. No eff
fectual prevention 10 known. but the
burning Of diseased plants and the de-
struction Of the beetles are indicated.
A spot upon the leaf and fruit Of cu-
cumbers is found In the east and IL
likely to cause trouble to pickle grow
ers in Ohio. Spraying with Bordeaux
mixture is indicated for this disease.
as we'll as for new leaf-baight Of the
musk-melon. causing many rather
large. dried spots in the leaves. follow
ed by dying and curling under from the
tips and margins. Tomato leaf-mold is
the most common fungus disease Of to-
matoes grown under glass. This caus-
ed serious loss in the station green
houses in 1891. where 1t was introduced
in an old plant carried over, from
which it spread throughout the houses
The disease first appears as rusty
brown patches on the under side Of the
leaves; as these patches enlarge the
leaf becomes yellow, willis and finally
dies. In cases Of severe attack the
whole plant may perish. and in any
case its growth will be seriously check.
ed. With leaf-mold. as with lettuce
rot, thorough ventilation is required
and spraying with diluted Bordeaux
mixture is indicated. Greenhouse to.
matoes are subject to other forms Of
leaf blight and spot, some Of them at.
fecting fruit AZ well as foliage. AL
diseased plants should be at once re.
moved and burnt.
The bulletin Is q report of progress.
in the study Of plant diseases, many O
them but little known. and in ease o
serious outbreaks Of such diseases gar
deners are requested to aid the station
in further study by sending samples O.
diseased plants to the experiment sta
ton at Wooster. with full description
of soil, treatment. etc.