Trimming tree shoot at trunk

[Stevo0523]

Hello. I am new to this form so please welcome me and my ignorance!.

 

I have a beautiful green maple with a rather large shoot coming off the stump and from what I am told I should cut this off to get better health to my tree.

I am wondering is how should I go about cutting it off?

Should I cut it off right flush with the tree trunk or should it come off a couple inches and also should be a straight cut with some shears or an angle cut etc.?

 

[Lowestoft Firewood]

It will probably take over the tree if left. 

 

Cut off nice and flush, if you leave a stub it will sprout more easily. 

[Gnarlyoak]

Nice straight flush cut at base of the growth will allow you to remove it without adversely affecting the tree.

If you have some hand shears or a pair of scissors then cut the grass down growing around the base of the tree as well while your at it. Even better if you consider removing the turf completely in a 0.5 - 1.0m radius around the tree and added a mulch in its place. 

[Stevo0523]

Thanks everybody for your help I took all your suggestions.