Acer - Maples and Sycamore
The Acer family are not considered native to Ireland, although the Hedge Maple (Acer campestre) is native to England. The Sycamore (Acer pseudoplatanus) is very widespread today across Ireland, having been introduced probably in or around the 17th century, from central or southern Europe. These trees are principally entomophilous (insect pollinated) and bear masses of flowers in bunches. Pollen production per flower is not high, and the pollen does not appear to travel far, but the large number of flowers partially makes up for this. Godwin suggests that high occurrences of pollen may be found where the trees may have concentrated. Hedge Maple Acer campestre does grow in woodland, seemingly preferring companionship with Ash (Fraxinus), but prospers in more open hedgerow and scrub environments, appreciating higher levels of light. Sycamore Acer pseudoplatanus, is a much larger tree and grows well in Ireland, profusely even. The seeds germinate readily, and as a consequence it is extremely common in woodland, hedgerows and ditches, field boundaries, gardens, even growing through paving, in yards, and on old and neglected buildings.
Pollen grains are tricolpate, sometimes tricolporate, and prolate in overall shape i.e. longer than wide. Polar length 20-50 microns, generally c.35 . Surface texture is striate/baculate.
