Show ALFALFA WEEVIL ITS LIFE HISTORY by W W OWENS U A C extension service if ac one wanted to produce I 1 large aggs numbers of alfalfa leevi is he would choose a thin stand of alfalfa as the ideal breeding ground the woodil fttie vil multiplies much tas taster tar in III a field where the billal ant nt are some diata ai ap art rt ith bare iacre spots in between than it does where the alfalfa is so thick thatis that it completely covers and shad shades the ground all female weevils seem to be endowed by nature to lay large numbers of eggs heat Is the fac tor which determines when they lay and how low many eggs they lay warm warin weather promotes egg la laying while cold weather retards regards ty it t assume that temperature of the air over an alfalfa field is 75 d degrees fahrenheit the tem temperature pera on moist ground which Is shaded by a heavy stand of alfalfa will be ae 65 degrees F P the temperature pera ture on the ground next to a bare spot in a tn stand of alfalfa will be 87 degrees es P the adult female weevil lives on the ground and lays her eggs in dry stems on the ground and at the base of growing alfalfa stems in the field of heavy hay where tile the temperature Is ig 65 degrees F p the weevil will be slow blow in starting to lay eggs she will perhaps per naps lay a total of eggs only during the season the time required for eggs to hatch Is also dependent upon lupon heat beat tile the eggs in this field w will ill take five weeks to hatch into the worms which do the damage in the field where there Is it a light stand of alfalfa with a temperature of 87 degrees F P down where the adult weevil lives egg la laying ying will be hastened each bach female weevil will lay about eggs twice as many as she would in the heavy hay where it is colder the tha eggs will hatch in two and one halt to three weeks not mu much r 11 more than halt half the time required in the other field A little arithmetic applied to the above figures will show that the damage in a thin stand of alfalfa whore where there are only halt half as many plants as in a heavy stand is not just twice as ag much but Is actually more than tour four ti times in es as much the damage occurs earler in the thin stand of alfalfa because the weevils hatch earlier the plants are less liable to withstand injury than they would be later for protection from weevil injury as well as for higher yields of hay per acre plow up the oll old thin alfalfa fields and replaced replace them with young heavy stands |