Bats and spiders are generally not “top of the list” animals when producers think about creating a healthy farm. But every farm should provide habitat for them because of the pest control benefits they provide.
Bats: Most bats are insect-eaters. Found in every state of the U.S., bats prey at night on adult forms of critters that 
farmers don’t like—armyworms, cutworms, codling moths, cucumber beetles, stinkbugs, June bugs, and mosquitoes.
Bats can be invited onto a farm by putting up a bat box, or by making simple modifications to a farm building. For more information about bat habitat and which bats live in your region, contact your state Fish and Game Department or Bat Conservation International, www.batcon.org/home/default.asp
Spiders: Like bats, spiders are generalist predators, devouring many kinds of insects. For centuries the Chinese have augmented spider populations in field crops as a pest management strategy. Spiders are able to rapidly colonize an area by parachuting on a silk thread—a practice known as ballooning. Spiders are often the earliest predaceous colonizers of agricultural fields.
Unlike insects, spiders have a soft external skeleton, making them more vulnerable to extremes of temperature or humidity, so mulching or no-till cropping techniques help promote spider populations. A study in Germany found that mulch increased
spider densities in wheat fields, and thereby reduced cereal aphid populations by 25%. Researchers have also noticed an interesting fact about spiders: their presence causes some insect pests to abandon their host plant, decreasing damage to crops. This has been observed for cucumber beetles, Japanese beetles, cutworms, greenbugs, leafhoppers, planthoppers, and for moth larvae in apple orchards.
Spiders often kill more insects than they can consume, but each species of spider has its own food and habitat preferences. To attract a wide range of spiders that will prey on many different kinds of pests, farmers can plant hedgerows in or adjacent to fields. It’s a good idea to include perennial and annual plants of different heights, as well as groundcovers and mulches.
If a pretty poster and a cute saying are all it takes to motivate you, you probably have a very easy job. The kind robots will be doing soon
