Note 1: (pollards)
The American Heritage Dictionary defines pollards as: A tree whose top branches have been cut back to the trunk so that it may produce a dense growth of new shoots.
Pollarding is the cutting of the top of a tree's branches back to the trunk, leaving club-headed stems that grow a thick head of new branches. The purpose in some areas is to limit the area of top growth or to create an annual harvest of boughs for basket weaving, securing thatch, and the like. In cities such as London it is done to prevent branches from tangling with overhead wires and from overhanging streets and to promote growth of a denser foliage.
Note 2: (disagreeable, old maid)
This comment by Emma is particularly interesting, because it is being written by a woman who is herself a single woman, with a very narrow income. During the writing of Emma, Jane Austen was the thirty-eight year old, unmarried daughter of a deceased clergyman, living in reduced circumstances with her mother. This is almost exactly the situation of Miss Bates. The difference is that the Austen women had the wealthy Edward Austen Knight, Jane's brother, to help them financially.
As a spinster, did Jane Austen suffer from the proper sport of boys and girls? If so, why write this? and why write in a way that, on the face at least, condones the children's behavior?
This gives a glimpse of how Austen must have dealt with her old-maid status: humourously, but perhaps with a tinge of bitterness or sadness.
Note 3: (sixpence of it)
At this time a shilling was equal to twelve pence; therefore, Emma is saying that Miss Bates would give up half of what she possessed.
Note 4: (recal)
A strange spelling, or a typo: recall is usually spelled with two l's in modern usage.