I would at least put it in a giant pile somewhere, and let it age for about a year, and then put it on the beds as mulch with some nitrogen fertilizer (the act of rotting uses up nitrogen). I googled it, and it said it was great mulch/fertilizer.

Re the tree being "protected", I don't think that means that you have to let it get dead and fall on your house. I would call a licensed arborist to look at it from your side - they should know what the law is, and might be able to give you some tips about how the part overhanging your property could be pruned without hurting the tree. We have two giant (over 60 ft tall) scarlet oaks, both right next to the property lines (my husbands ancestors were sneaky that way), and have many times had them pruned, and one neighbor actually shares the expense with us, because it was overhanging his house, and his insurance company didn't like it. Both trees are still going strong.

Jackie

IMO oak leaf litter is a superb mulch. I started off using it with acid-loving plants because I have an alkaline soil. I was under the illusion that it would be beneficial in that situation. Well it is, but it doesn't do anything one way or the other for pH. When broken down it is neutral just like other decomposed mulches and composts. Pine needles, too, darn it. I now use it on a bed that includes blueberries, roses, and assorted perennials. They all look very healthy.

In my area we mostly have coast live oaks but valley oaks ought to be good, too. If the leaves are big (I don't think they are), then run over them with a mower to break them up. And if you don't have a good place to use them, put them in your compost bin. What you do not what to do is mix them into the soil. They need to be on top, or in a compost bin breaking down. Just don't waste them. They are gold for the garden.

BTW, did you know that oak trees will be healthier if they have oak leaf litter below them? The leaf litter supports the correct soil microbes for California oak health. Grass-type mulches do not work well for oak trees.

It might be that your neighbor could get a permit to prune the part of the tree that overhangs your property so that it doesn't represent a hazard to you. I suspect they won't be allowed to remove the entire branch, but they could shorten and lighten it so it is less likely to break off and fall. Who would pay for this work the two of you could work out together. Maybe 50-50 split.

Rosefolly

Jackie,

In this town and this county, there are so many laws and rules about those silly trees, even when they are bird planted and the foolish landlord puts a concrete patio all round it so it can die/rot and land on his own rentals.

I don't really want to put a lot of money in to fixing their tree, when it falls...it can be their issue.

Other than the top layers, we have not touched the lower layers of leaf litter in years-10"+ deep, the newer stuff is heading to our compost bin for next season.

I would love to spend the money to have a couple of trees pruned up and look better, but not sure I want to spend the $$ on that tree.

Thank you Rosefolly for the litter input! I know the oaks need the litter so we are leaving it on one side of the shed, where it killed a couple of duplicated fruit trees already. But part of it needs to go.

I am hoping this neighbor deals with the oak when he deals with the completely dead (pine bark virus killed) tree that is hanging over a major road. He has been made aware of both. Now he has to decide what to do.

We made our neighbor aware (many times) that the Italian Stone Pine limb that extended all the way across our property from his tree was dangerous, would eventually self-prune, and would cause some real damage.

We offered to pay for the trimming, with his permission.
NOPE. He would get it done himself. Eventually.
This went on for years, and eventually the tree was brushing our fireplace.
That's when it came down, in the night, taking out our arbors and fences, and filling up half of our front yard.

It cost him a MINT to have it cleared out, and our fencing repaired. Things here are still not back to normal.

He was a tad testy about it, but he WAS liable.
It'd have been cheaper and easier to give us permission to trim it back.

Jeri

I had a client in the Santa Clarita Valley who used to have to blow off his roof every week because of the six old oaks the house was built under. He had a dumpster to haul off all the extra litter as there was SO much of it. Keeping the pool clean of that stuff was a continual issue. But, he had SOIL! Those oaks are hundreds of years old. The house was built long before there were any rules about not molesting the oaks. I never bought any amendments for that garden. All I had to do was go out past the pool, scrape off the new stuff and shovel up the dark, black, wet stuff from underneath and use it everywhere. I actually hauled a bunch from that house to several of his friends' gardens who were also clients. Why buy something made from ground up trees when you HAVE a ton of what Nature intended to amend the soil? It's great stuff.

What would kill other plants would be the shear tonnage of what large oaks drop. They smother competition. At least it isn't Eucalyptus litter. That stuff is obnoxious and toxic to most other plants. Kim