Hey looking for command that controls size of Brush in Foliage Tool. Thank you in advance All the best!
You can see your shortcuts under Edit → Editor Preferences → Keyboard Shortcuts. You can there also set your own preferable shortcuts:
In this image I have searched for Foliage to see what I have as shortcuts for the brush size 
Thank You for the answer but would like to push above
that value : 65536
would like to cover all the area 
shortcut instantly back to 8192
Then if you select it and write the number yourself to something (eg 80000) you are able to override it. This works for most cases in UE
But shortcuts does not seam to work for values above the caped ones.
This might make your project crash if you don’t have a super computer, because it will be a lot of data to handle at the same time.
Not a problem 
- typing stops at this value ive mentioned