1170 
aged, 
aged, and enlist the energy of every orchid culturist, 
not necessarily for the production of hybrids alone, but 
also for the reproduction of rare species and varieties, and 
a number of species which are fast decreasing or becom- 
ing extinct in their native homes. Aside from the finan- 
cial inducement offered the commercial grower, it will 
ORCHID 
apices and on new growths of deciduous and plicate- 
leaved species, indicate either lack of sufficient water 
at the roots or an overdry atmosphere, both of which 
conditions can be easily changed. 
Snails and insects.-orchids are attacked by many 
forms of snails. Insect pests are a great annoyance 
prove instructive to the botanist and afford infinite 
pleasure and pastime for the amateur. 
z)i.«eases. -orchids are subject to many diseases. 
Those having importance from a cultural standpoint and 
most troublesome to the grower are known as wet- and 
dry-rot and spot. Wet-rot is caused by an overmoist or 
stagnant atmosphere, and is usually first detected by a 
semi-transparent appearance of the parts afpected, which 
soon become dark brown. It spreads slowly along the 
tissue. If noticed at the commencement it can be 
readily checked by slitting the epidermis with a sharp 
knife and removing the plant to a more airy position in 
the house for a few days. Dry-rot is caused by a fun- 
gus which attacks the rhizome of the plant. It is often 
produced through burying the rhizome or base of the 
plant with compost. Cypripediums are subject to it. 
Large, healthy growths when attacked quickly Show a 
sickly pale color in the foliage, which, on examination of 
the base, will be found discolored, and with a light 
brown appearance. If the portion attacked is quickly 
removed with a sharp knife it will usually give no fur- 
ther trouble; otherwise it will travel through the en- 
tire rhizome and destroy the plant in a very short time. 
Spot comes from various causes: the appearance of 
small dark brown spots on the succulent leaves and 
pseudobulbs is usually an indication of cold and over- 
watering. Spot also arises through weak tissue, espe- 
cially in phalaenopsis, saccolabiums and angraecums 
during winter, which have been grown too warm, shady 
and moist. the affected parts should be slit with and laelia. 
sharp knife and a little flowers of sulfur should be 
rubbed over the wound. When they make new growth 
the plants should be placed in a brighter and more airy 
pOsition to induce a better growth. The brown dots which 
make their appearance on the leaves, especially at the 
to the cultivator. They can be kept in subjection only 
by constant attention. Slugs and shell snails are very 
destructive. If allowed to increase they devour young 
shoots, roots and flower-buds. the best means of captur- 
ing them is to place saucers of dry bran on the shelves 
among the pots, and look them over morning and even- 
ing. By this means many will be destroyed. Various 
species of scale insects attach themselves to the leaves, 
pseudobulbs and rhizomes of nearly ■..:]. species of Or- 
chids, and can be eradicated only by the use of a soft brush 
and washing with a sponge and water A little whale- 
oil soap added to the water i- of great assistance, and 
also useful in destroying red spider and green and yel- 
low fly. Black and red thrips attack the young growths 
of many species and often become very troublesome. 
Fumigating the houses with tobacco stems lightly about 
three times during the week Will soon cause them to dis- 
appear. Fumigation is also a sure remedy for green fly. 
The Cattleya fly is very injurious to young growths of 
Cattleyas, ltelias and some Epidendrums. The flies 
lay their eggs in the very young growth at the base, 
causing an enlargement which is easily distinguished. 
The only remedy is to remove the growth, and burn it. 
The mature fly can be eradicated by fumigating the 
house with tobacco .stems about three times each week 
during early spring. 
The Dendrobium beetle larva burrows in the stems of 
various species of the genus, and is detected by a small 
discolored spot. There is no remedy, except to cut 
away and destroy the parts attacked. An insect which 
is much more to' be dreaded is the dendrobium mite, 
which perforates the canes and rhizomes of dendro- 
biums and many other Orchids, laying a number of 
eggs in each perforation. on hatching, these eat away 
a part of the plant around them, causing that portion to 
decay. They can be found only by careful and close 
observation, and this often after the plant is beyond 
redemption. There is no remedy but cutting them out, 
and unless the plant attacked is valuable it is best to 
burn it and keep the pest from spreading. 
Mealy bug is usually not very troublesome to Or- 
chids. ' It is readily seen and destroyed without much 
injury to the plant. 
Roaches are usually very troublesome, and hard to 
eradicate, as they feed at night and remain hidden 
through the daytime. They destroy roots, growing 
shoots and young flower-buds and scapes. Bran, pow- 
dered sugar and Paris green, mixed together and placed 
around the houses in saucers, will usually keep them in 
subjection, and they should be hunted down at night 
by the aid of a lantern. Many can be caught in this 
manner. 
Sow bugs or wood lice are usually common in every 
part of Orchid houses, pots and baskets. They do a 
great deal of damage to young leaves, roots and the ten- 
der portions of flower-scapes. The Paris green mixture 
used for roaches is very effectual in reducing their 
number, but it is impossible to be entirely freed from 
them- robert M. GREY. 
