I am trying to breed alder as a grain crop. One of my ideas is to
cross A. incana (the native alder) with A. cordata ("Italian" alder,
widely planted in municipal settings for its handsome dark green
leaves) which has much bigger cones.

To do a cross you have to keep out rogue pollen. A friend gave me
Glassine Bags, H86065, they are widely available from all sorts of
suppliers, but I bought more from r s components, who are mainly an
electronics supplier, because I already had an account with them.

I cut the catkins off and put these bags over the cones and sealed
them (the bags I have may have deteriorated in storage, the flaps
weren't very sticky, so I used Sellotape) and left them. But after
only a few days the cones poked through. The "paper" of the bags had
not turned to pulp or to mush in the rain. What seems to have happened
is that bags flapped in the wind and where the cones touched the bags,
they rubbed through.

Does anybody have any recommendations or good ideas for how to get
round this? There is still time before A cordata becomes fertile in
Northumberland.

Michael Bell

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