Is Alder Leaf Beetle Extending Its Food Plant Again ?
Posted: Tue Apr 22, 2014 10:35 am
Is Alder Leaf Beetle Extending Its Food Plant Again ?
Since the Alder Leaf Beetle (Agelastica alni) was re-found in Greater Manchester a few years ago (2004) it has extended its range in our area considerably, now covering most of Cheshire and Merseyside.
During that time period it has been seen to use English Alder (Alnus glutinosa) as its primary foodplant but has extended its food resources by encompassing both Grey Alder (Alnus incana) and Italian Alder (Alnus cordata). Beetles and larvae can now be found regularly on all 3 species of Alder.
However, this year (2014) I visited the area surrounding Town Park Lake in Runcorn (SJ545826) and found 10's of thousands of Alder Leaf Beetle adults on the English Alders around the lake. Then, I began to notice that the Hazel (Corylus avellana) trees round the lake also had Alder leaf beetles, in a somewhat lesser profusion, on their leaves AND the leaves displayed the same shot-hole feeding patterns as the English Alder leaves. Agelastica alni were feeding on the Hazel !!
Don, have you noticed this behaviour and if so when and where - it is the first time I have seen it. If this extension of foodplant is viable will we see another 'explosion' of Agelastica ??
Steve
Since the Alder Leaf Beetle (Agelastica alni) was re-found in Greater Manchester a few years ago (2004) it has extended its range in our area considerably, now covering most of Cheshire and Merseyside.
During that time period it has been seen to use English Alder (Alnus glutinosa) as its primary foodplant but has extended its food resources by encompassing both Grey Alder (Alnus incana) and Italian Alder (Alnus cordata). Beetles and larvae can now be found regularly on all 3 species of Alder.
However, this year (2014) I visited the area surrounding Town Park Lake in Runcorn (SJ545826) and found 10's of thousands of Alder Leaf Beetle adults on the English Alders around the lake. Then, I began to notice that the Hazel (Corylus avellana) trees round the lake also had Alder leaf beetles, in a somewhat lesser profusion, on their leaves AND the leaves displayed the same shot-hole feeding patterns as the English Alder leaves. Agelastica alni were feeding on the Hazel !!
Don, have you noticed this behaviour and if so when and where - it is the first time I have seen it. If this extension of foodplant is viable will we see another 'explosion' of Agelastica ??
Steve