Sept. 15, 1925 
Reaction of Grasses to Chinch-Bug Attack 
583 
Among the plants with, tender tissues, there was only one species, 
Sphenopholus obtusata (row 88), which showed but slight damage. A 
few species, for example Bromus arvensis (row 6), showed only 
moderate injury. The majority of tender grasses were either severely 
injured or completely killed. 
One instance is noted, in the case of Hystrix hystrix (row 35), in 
which the age of the grass seemed to make no marked difference in the 
ability of the plant to withstand injury. Row 35 was a 2-year old 
stand of Hystrix hystrix seed of which originally came from Indiana. 
Row 73 was composed of seedling plants of the same species, seed of 
which was received from Idaho under the name of Hystrix patula 
and so listed in the plots. Resistance was no more noticeable m the 
2-year-old strain than in the 1-year-old strain, for both were killed. 
No correlation is apparent between habit of growth (that is, 
whether the plants are tufted or bunched) and the degree of injury 
and recovery. Bunch types were alike slightly injured or killed, 
and the same can be said of the turf, tufted, and dispersed types. 
The date of maturity of the various species has been listed herein 
because it was noted that several species had matured and produced 
seed before the migration of the chinch bugs from the wheat to the 
grasses. This fact may have an important bearing in badly-infested 
areas where the production of an early seed crop is desired. 
No correlation is seen between habitat and degree of injury, 
although it is important to note that some grasses which occur as 
pests in cultivated fields, such as Aegilops cylindrica (row 100), may be 
killed by the bugs. Others which occur in plowed fields, such as 
Lolium temulentum (row 53), may mature and produce seed before the 
insect attack begins; while grasses like Festuca elatior (row 68), also 
found in cultivated areas, may show only moderate injury and 
marked recuperative powers. 
SUMMARY 
During the season of 1924, the grasses in the grass garden of the 
Kansas Agricultural Experiment Station were attached by large 
numbers of chinch bugs which migrated from adjacent wheat fields 
after harvest. The different species showed different degrees of 
resistance to injury, and later some of them exhibited marked ability 
to recover from the attack. It was apparent that native perennial 
species with harsh tissues were able to survive chinch-bug injury 
and showed the most marked ability to recover. These grasses 
comprise about 80 per cent of the native prairie grasses of Kansas. 
Besides the data regarding the resistance and recovery of the 
grasses, a large number of species of grass not heretofore recorded 
as host plants of the chinch bug are listed. 
