On September 9th I came across a tree nearly covered with house martins. They were flying around and in and out of the tree, and even perching on its twigs. I had never seen so many. Was it a sudden abundance of aphids?
Fons Jasper, Portlaw, Co Waterford
The house martins were gathering into a flock before migrating back to Africa.
I'm sending you a photograph of what I believe to be a cornflower, which nowadays are very rare. Where did they all go?
Donagh Cronin, Fermoy, Co Cork
They became almost extinct because of agricultural practices. They grew among grain crops and were regarded as weeds. They are returning now mainly where ground has been disturbed, such as in road widening or reclamation.
I saw the creature in my photograph moving quickly on the lawn. It was 10cm long and yellow, with dark-blue diagonal stripes on it back.
Kathleen Gleeson, Killarney, Co Kerry
It is the caterpillar of the death’s head hawkmoth, a summer visitor from Africa that will pupate now in the ground, but the pupa will hardly survive the winter.
My son and I have been spotting some spiders recently. The one in the photograph I'm sending you has been taken through the web and is eating a fly.
Liz Whoriskey, Dunboyne, Co Meath
It is the garden spider.
My mother-in-law has a brick-coloured spider in her garden. It made a huge web about 30cm wide.
Liam Crowley, Bandon, Co Cork
It, too, is a garden spider. They can vary from black to ginger but are more usually light brown with dark markings.