In all the years we have been spreading wood chippings from our trees across the garden we have never noticed any Nitrogen depletion at all.
If you are worried, and personally I don't think you need to be, then you could sprinkle some Blood, fish and Bone on the ground in Spring.

Bit cheeky of the tree surgeon - they should take the chippings away, but that's expensive these days. If he wasn't going to do that, he should have told you beforehand.

Now they're down, it won't be an issue all winter, but if it was my woodland garden, depending on the planting, I'd go out with Growmore (not FB&B cos it attracts foxes, dogs, cats, vermin and any other animal roaming about if its applied to the surface, though if you live in a rural area, it won't be so much of an issue) granules in spring and liberally apply to the soil, raking it in as far as possible. The nitrogen issue won't be a problem if its just trees and very large shrubs though - its only the smaller, ground cover types that might suffer a bit, so if its principally large plants, I wouldn't worry too much.

Regarding Fish Blood and Bone, I get through a lot of it when planting - it goes in the bottom of the hole, but I never apply on the surface. But then I live in London, where foxes abound and there are probably only slightly fewer cats per square mile as people... and that's not mentioning the rats, who appear at night to grub around in it.

Never had any problems with FBB here and we have all those critters visiting the garden, but then, I usually rake it in.
Any Nitrogen rich fertiliser would do the trick.

Here, I would recommend a vegetable-based fertilizer, such as alfalfa meal, or cottonseed meal. I don't know if there is an equivalent in the UK.

As long as the chips remain on the surface and are not tilled into the soil there won't be much nitrogen depletion at all, not enough surface area for that. If the chips contain some live green wood they will probably give some nitrogen back so you break even in this whole matter. With regards to the horse chestnut tree there is always a chance of spreading bleeding canker so I can see why he did not want to remove the chips from your property if there are ordinances that keep their removal punishable by a hefty fine.... and the tree surgeon would be aware about this. In any case you should have been questioned first upon the details of chip removal or dispersal.

Don't worry about the nitrogen issue at all. The nitrogen uptake by the wood chips is only temporary and re-released back into the soil once decomposition is complete. This provides available nitrogen to your plants in a slow & steady manner - just as your plants need it. Adding supplemental nitrogen could be harmful. Your plants don't need it anyway if they are dormant.

Normal rainfall brings down nitrogen from high up in the atmosphere and replenishes the ground. That's the good stuff.

'Adding supplemental nitrogen could be harmful' - REALLY, Bathgate? Under what circumstances, precisely? Have you a source for that information? Because it's certainly not what my horticultural lecturer taught me all those years ago when I was doing the RHS M. Hort... and I've been adding Growmore to both mine and clients' gardens in spring for years, with or without mulch.

Pauline 49, it won't be at all harmful to add some Growmore in spring, and rake it in, if you think the area needs it, the NPK is only 7-7-7 anyway, and its therefore balanced.

An excess of nitrogen will promote rapid green vegetative growth at the expense of root development & fruiting/flowering. The result is a big green plant that will flop over because it hasn't got a root structure to support it, never mind fruit production. If it's just green plants you are growing anyway, keep those pruning sheers close at hand, you'll need them often.

Healthy plants require a balance of primary nutrients, secondary nutrients & micronutrients and too much nitrogen will leach beyond the plant's reach and pose a health hazard to drinking water. That's not helping anybody.

The best source of nutrition for plants is the use of organic matter (mulch & compost) as they supply a slow & steady release of ALL nutrients through decomposition.

Well, Bathgate, all that you've said there is generally true - in this particular case, however, no one was suggesting dumping nitrogen on the area every couple of weeks, it was just a proposal to offset any possible nitrogen depletion from smaller plants caused by being surrounded with fresh, greenwood chippings, and only once in the spring. I don't know what you think, but in my book, that certainly doesn't qualify as a nitrogen overload. Growmore breaks down within six weeks, and its NPK is 7-7-7, in case you're interested.

Happy Thanksgiving, Bathgate and Loosestrife!
Here in the desert, we feed well and often, partly because of the frequent watering we have to do, and partly because of the way denitrifying bacteria go berserk in our hot climate. In cooler and moister climates, nitrogen remains longer in the soil, and it is easier to overfertilize. In the wild in such climates, nitrogen levels in the soil are normally moderately low, maintained by plant litter, dead bugs (and other animals), assorted "manures", and moderate populations of nitrogen fixing bacteria. Native vegetation survives quite well on such fare, but gardening normally looks for more than just survival. We fussy gardeners want dense hedges, fast growth--at least soon after planting--repeat bloom, and no dead branches and yellowish leaves! When we do this the impatient way, we sometimes pay for this in nitrate runoff, frequent pruning needs, more frequent infestations of fungi and insects, and brittle wood and floppy stems. Better to take a deep breath, practice some moderation, and use slow acting and organic nitrogen sources only when necessary. Unfortunately, low nitrogen organic matter--such as wood chips--tilled into the soil may make adding nitrogen more necessary. Just leaving them as a mulch will deplete the nitrogen near the soil surface, but leave the deeper level's content intact. Eventually, it will support populations of free-living nitrogen fixing bacteria, which will ameliorate the problem.

Happy Thanksgiving

The same to you and your families Tug and Bath!

Thank you Loosestrife2, Same to you and yours.