Done.
I'm not an iD users - so I did it with JOSM.

Hi,
The nodes with the tag arboretum=yes look like individual trees? Might be better tagged natural=tree - this is for significant trees and I'd take it that is the case if you have tagged them as individuals?
An arboretum is usually a collection of trees - so an area. That is what has attracted me to the tag you used. But I think arboretum=yes would be a sub tag under another tag and that is not what I want. I think the following might be usefull for arboretums;

landuse=arboretum
and/or
leisure=garden, garden=arboretum

Arr, sorry may not have tracked who made the tag originally?

Was told once that I was the last person to touch something so I was responsible for it.. ummm not certain that is totally correct.

Hi,
Why not make these ponds one area? It would solve problems with overlapping ways.
If there are gaps between these area they they are not evident in the ways you have put in.

Hi,
On Way: 613922075 you have tagged landuse=scrub.
I have not changed it, but I think it should be tagged natural=scrub.
See natural=scrub

Hi,
On Way: 221467102 you have tagged landuse=scrub.
I have not changed it, but I think it should be tagged natural=scrub.
See natural=scrub

Hi,
The tag landuse=scrub I think it should be tagged natural=scrub.
See natural=scrub

Hi,
On Way: 248048284 you have tagged landuse=scrub.
I have not changed it, but I think it should be tagged natural=scrub.
See natural=scrub

Hi,
On Way: 459779977 you have tagged landuse=scrub.
I have not changed it, but I think it should be tagged natural=scrub.
See natural=scrub

Hi,
On Way: 254491816 you have tagged landuse=scrub.
I have not changed it, but I think it should be tagged natural=scrub.
See natural=scrub

Hi,
On Way: 356375516 you have tagged landuse=scrub.
I have not changed it, but I think it should be tagged natural=scrub.
See natural=scrub

Hi,
On Way: 61192637 you have tagged landuse=scrub.
I have not changed it, but I think it should be tagged natural=scrub.
See natural=scrub

Hi,
On Way: 545490074 you have tagged landuse=scrub.
I have not changed it, but I think it should be tagged natural=scrub.
See natural=scrub

Hi,
On Way: 411212810 you have tagged landuse=scrub.
I have not changed it, but I think it should be tagged natural=scrub.
See natural=scrub

Hi,
On ways 410478440, 411483863, 411454355, 411444715 and way/410476931 you have tagged landuse=scrub.
I have not changed them, but I think they should be tagged natural=scrub.
See natural=scrub

Hi,
On Way: 411099606 you have tagged landuse=scrub.
I have not changed it, but I think it should be tagged natural=scrub.
See natural=scrub

Hi,
On Way: 410778807 you have tagged landuse=scrub.
I have not changed it, but I think it should be tagged natural=scrub.
See natural=scrub

Hi,
On Way: 246876954 you have tagged landuse=scrub.
I have not changed it, but I think it should be tagged natural=scrub.
See natural=scrub

Hi,
On Way: 210359791 you have tagged landuse=scrub.
I have not changed it, but I think it should be tagged natural=scrub.
See natural=scrub

Hi,
On Way: 263281792 you have tagged landuse=scrub.
I have not changed it, but I think it should be tagged natural=scrub.
See natural=scrub