You should always consult your insurers about this. Some like you to warn people not to go too close, others do not like it.
Irrespective of whether people really do get stung or not it can invite 'opportunist litigants' (the insurers words) and I have actual experience of that.
15 years in one place at the heather, then a couple who asserted their right to roam went right through between two row of hives, someone got stung, and besieged the owners with complaints about these hive interfering with their rights..
So...the estate factor...to avoid hassle....insists we put up warning signs. Within the season we had 6 claims through certain companies. One couple claimed to have been stung in excess of 200 times each, required expensive treatment and had to take three months off work, and the woman was suffering from ongoing trauma issues which could be long term and require care. The man lost his privately bought glasses, cost in excess of 3000 pounds. Or so they said.
Fortunately my insurers still partially covered the risk (I was held 50% negligent for inviting opportunists...which the other 5 claims turned out to be and were rebuffed) so they had the couples medical and work records investigated.
The had gone to hospital after the event, and the medical notes showed that the woman had been stung twice and the guy not at all. They had in fact been nosey and had disturbed a hive. There was the medical matter of two hours at A&E and discomfort for the woman for a few days of their holidays. There had been no time off work and no ongoing trauma. There was no available purchase record for the glasses, only a quotation for special glasses dated AFTER the event.
Although not stated in the response to the case the insurers rep said this was not unusual, and that most of the severe 'medical' records and other costs would have been 'arranged' on their behalf by the claims company.
Anyway we got away with a small (300 pounds) contribution to compensate for the spoiling of their holiday in return for them just going away. Some insurers just pay out as its cheaper to do so.
We are currently in discussion with one of our estates who are now requiring signage at the behest of THEIR insurers (hence passing the risk to us) and do not yet know what the final wording must be but it has to include some reference to 'proceeding beyond this point is entirely at the persons own risk'. Its legally grey to do so but deters many from venturing through.
Just be very careful what is said. Your association insurance should cover it if you have not done or said anything to invalidate it...hence it's important to ask.