Is this oak bracket? How bad a sign?

[daltontrees]

1 hour ago, CathB said:

Thanks hugely all, I really appreciate your knowledge and thoughts.

 

We need to cater for both the future of mature trees & the stock beneath which is sheep most of the year, and heifers for a few months in the summer. We've lost two of the seven oaks in the last 2 years, so just trying to work out how to best preserve the rest - fencing is a option but it's minimum 75m for the smallest canopy & I'd prefer to do post & rail wood vs cheaper stock fence as 16 apartments (an old Hall building converted) look out onto the park field. But the cost is ££ for 5 trees, so I'm trying to work out which to prioritise - hence seeing the ganoderma resinaceum on one which complicates it if it's already compromised the trunk. Decisions!

Doesn't look like resinaceum to me, looks very much like adspersum. If so, mildly parasitic, will probably do for the tree eventually but not anytime soon. I've had one on the edge of a paddock recently absolutely covered in brackets. The solution is to reduce the height as early as possible so that you're not adversely affecting its ability to fight off decay too much but seeing off the risk of windthrow in the longer term. A height reduction might be cheaper than fencing.