A countryside management volunteer I follow on FB wrote the following
"It is that time of year when social media is again flooded with 'helpful' suggestions to take unwanted pumpkins to the local woods or park, or to put them out in the garden for wildlife.
I would urge you to please not dump pumpkins in local woods or park.
Firstly, you have no right to dump your waste food on land owned by someone else. At the very least have the curtesy to get the agreement of the landowner first.
Secondly, autumn is the season of nature's bounty – the countryside is full of seeds, nuts and berries - the wildlife does not need your pumpkins.
Thirdly, the additional nutrients carried by pumpkins and other forms of organic waste can alter soil nutrient levels and have a detrimental impact upon the flora.
Fourthly, far from helping wildlife it can make some, such as our declining hedgehogs, ill if they eat it! (which could be fatal so close to hibernation when condition, bodyweight and fat reserves are crucial to survival).
Lastly, dumped food attracts rats and the diseases they spread.
If you wish to risk attracting rats into your own garden that is obviously entirely up to you, although it might not impress the neighbours"