A study was made to compare the numbers of infective ovine nematode parasite larvae on an open pastured block and an adjacent block forested withPinus radiateat 200 stems per hectare. Each block consisted of two paddocks which had similar nematode parasite egg contamination. Infective larvae of six genera were recovered over a 12 month period viz.,Trichostrongylusspp.,Ostertagiaspp.,Cooperiaspp.,Nematodirusspp.,Chabertia/Oesophagostomumspp. andHaemonchussp. A significantly higher recovery ofTrichostrongylusspp. (p<0.01) andOstertagiaspp. (p<0.05) from the pine forested block was probably due to the more favourable climatic environment under the pines.