none Parasites diseases and disorders; Parasites; Insect parasites; Hosts; Ecology; Community structure; Habitat; Terrestrial habitat; Abiotic factors; Chemical factors; Land and freshwater zones; Palaearctic region; Europe Insecta; Hymenopteran parasites; Ichneumonidae; Insecticide effects on koino/idiobiont parasite dynamics; Forest and woodland, insecticide treatment; Effects on hymenopteran koino/idiobiont dynamics; Poland; Ostrow Mazowiecka Forest District; Insecticide effects on hymenopteran parasite dynamics, forests Ichneumonidae; Insect hosts; Koino/idiobiont parasite dynamics; Effects of host control treatments; Relative abundance; Population dynamics; Koino/idiobionts, effects of insect host control treatment; Forest and woodland, koino/idiobiont population dynamics; Effects of insect host control treatments; Fertilizers and pesticides; Insecticides, effects of insect host exposure on koino/idiobionts; Poland; Ostrow Mazowiecka Forest District; Koino/idiobiont dynamics, effect of insect host control treatments, forests