

> ——§——@ 

THE STORY OF CACTUS a 

ground and will eat a new opuntia pad until the edges are all serrated. Others, 
such as the Hemipterae and Pentatomidae (calicoback) suck the juices to such 
an extent that the plant will wither and die unless they are given a good 
dinner of “Blackleaf 40” or any other good nicotine preparation. 
The yellow Mimorista worms (65) bore into the center of the plant and 
work down to the root and then the plant dies. When this worm gets into a 
plant, one never notices it until the plant dies and then it is too late. The 
only noticeable change in the plant is it loses its green waxy appearance but 
we do not advise one to cut open every one of their cacti that have this 
paleness as this may be caused by at least a dozen reasons. 
The deep blue Melitarias do great damage to the Cylindropuntiae, especially 
the Opuntia arborescens (25) and in some parts of West Texas and New 
Mexico, nine out of ten plants are affected with the black-puff-ball like masses 
of secretion, showing this worm is at work. This worm is easy to control if 
caught in time. Just cut off the branch so affected before the worm has a 
chance to get to the heart of the plant. If one sees the secretion on the first 
branch the plant can easily be saved. We once had a blue plant found in 
Arizona, which had not been classified and it showed the work of a Melitaras. 
We cut it back and did not cut back far enough. We cut again and had to 
cut the third time. This time we cut the plant close to the ground, a shoot 
came up out of the ground and we now have a nicer plant than we had before. 
Always burn these affected parts and cut back enough the first time. The best 
way is to examine the cut part left on the plant with a powerful magnifying 
glass to see if the worm has gdne on. A thorough sprying with Bordeau 
Mixture in 2-2-50 mixture or Commercial concentrated lime-sulphur with 
Arsenate of Lead will discourage the worms. 
If the plants are attacked by mealy-bug (Pseudococcus citri or P. longifilis) 
a good strong spray of water will wash them off. Then wash the plant with 
whale-oil soap and a weak solution of carbolic acid using a soft brush this will 
remove them easily. 
Nematode Root-gall (Heterodera radicicola) is a disease that attacks the 
roots and they knot and contort and the swellings when cut open, will show 
a red line inside. This is a true worm and the roots should be cut back and 
the soil be removed and either burned or taken far away. There are two treat- 
ments for soil which cannot be removed. One is sterilization by steam and the 
other by formalin, 
Red Spider (67) (Tetranychus bimaculatus) is just a nuisance and that is 
about all but they will suck scme kinds of Neomammillarias until they turn 
grey and die. They will spin a web over the plants and are easily removed 
by a strong spray of water. Dusting with dry sulphur will kill them. Spraying 
with Volck will also kill them. 
Aphides are ant cows and can be controlled with a kerosene emulsion and 
nicotine solutions, or tobacco dust or snuff dusted on them. 
Cactus cottony cushion scale is insects which hide in cotton-like cocoons on 
the ends of spines. These are best controlled by a solution of four ounces of 
pyrethrum (Buhach) dissolved in one gill of alcohol and added to twelve 
gallons of water. Spray every two weeks until they are killed. Volck will also 
kill them. 
Cutworms (Agrotis), arsenicals mixed with shorts and placed about the 
plants to poison or half inch holes punched near the plants to trap them. 
Shot hole (68) (Gloesporium lunatum) appears in little black spots on 
the platyopuntias (66) which spread over the pad, turning grey with time. 
Then the pad dries up entirely and drops off. The best way to treat this 
disease is to cut off the infected pads a ssoon as they appear and burn them. 
Cochineal (Dactylopius coccus) can best be controlled with a very strong 
needle spray of water with all the force one can give it. The male of the 
species looks like a small fly and the female encloses herself in a ball of 
cotton and looks like a fat spider but ts really a louse. When on the plant, 
she looks like a small bunch of cotton growing on the plant and was at one 
time an important item of commerce. Six million pounds sold one year for 
$4,200,000. 

54 A well planted bowl of cacti. 57 Echinocereus chloranthus in bloom. 
55 Bloom of Opuntia lindheimeri. 58 A bowl of cacti. 
56 Harrisia tortuosa in bloom. 

