Mr Ogilvy, who has been running his business in Mullion Creek for 30 years, has received phone calls from Orange residents who have mistaken inedible horse chestnuts for the edible commercial chestnut.

Horse chestnuts can cause nausea and sickness when eaten and can be found on trees throughout Orange.

“Horse chestnuts are poisonous but it would appear that half the Orange population thinks they are edible,” Mr Ogilvy said.

Last week, he had a phone call from an Orange resident who had mistakenly used horse chestnuts in a recipe.

He said others had sent boxes of the poisonous variety to friends and family in Sydney.

“We’re quite concerned about this,” Mr Ogilvy said.

“The population of Australia does not have chestnuts in its culture, which makes it easy to get the varieties confused.” Mr Ogilvy said there were distinct differences between sweet commercial chestnuts and horse chestnuts.

“The simplest way to tell the difference is by the leaves and the husks,” he said.

“You can’t grab the husks of sweet chestnuts because they’re sharp.”

Mr Ogilvy advised Orange residents to learn the differences between the varieties and avoid the horse chestnut.

“People should be advised not to eat them,” he said.