[john1412]

I've recently planted a Castanea sativa or sweet chestnut and I was wondering will the tree produce chestnuts or will i need to plant another one or two for pollination partners, there is a Aesculus hippocastanum, or horse chestnut tree in the garden as-well and i was wondering would they pollinate each other or will i need to get another sweet chestnut

[Greengage]

It produces both male and female flowers on the same tree and does not neeed another to pollinate it. Depending on the variety you have some produce single nuts and others two nuts per fruit. it is not related to the horse chestnut.
For me it does not make a proper tree as it is a bit messy growing limbs this way and that. they can be very long liived up to 1000 years so that should see you remembered by a few generations wheather they thank you or not is anyones guess. best of luck with it.

[tippben]

Yep, they are wind pollinated. Where I grew up there are vast tracts of chestnut coppice,retained for their value as building materials and charcoal. You'd need a good few to replicate that pollination, but using a plastic bag, shaking some male pollen in, then shaking the entire bag around all the flower clusters (put the flowers inside the bag) should help pollination.