Pine needles and cones as mulch?

At the weekend, I raked up the fallen cones and needles from beneath our Scots Pine. I haven’t raked up that area for at least a year. Can I use the material as it stands to mulch around another Pine which is suffering from being in a drier area or do I have to let it rot down a bit further?

 

They are fine to use now because they take a long time to breakdown. The biggest consideration is they don't do an awful lot compared to other mulches in terms of reducing water evaporation but won't do any harm and is better than nothing.

 

Your cat may 'appreciate' a nice easy scrabbing zone; just tell it not to!

 

Interesting to know it’s not as good at reducing water evaporation but I’m glad I can put it to use (instead of just leaving it in this pile) @Thevictorian

The cats may appreciate it, but the squirrels and foxes will appreciate it more and I might find next year’s horse chestnut or a rancid egg in it if I leave it as it is @infradig

 

They naturally fall in forests, and don't really add much other than a layer like the one you have, so there's not any great point in moving them.

If your other pine is suffering in some way, they won't really help it, especially if the ground is dry around it, which is probably the most common problem for pines if they aren't in suitable locations. Adding layers onto already dry ground never really helps to any extent, and can make a problem worse.
If it's a well established tree, it could have had damage of some kind, so any other info you can give will be helpful.
Photos of the other tree will also help, and you might get some advice on how to proceed with it.

 

Nice job on cleaning up the Scots Pine area! You can definitely use the fallen cones and needles as mulch, but it's a good idea to let them break down a bit first. Fresh pine needles can be acidic, so letting them rot down a bit will help neutralize the pH. Just spread them out in a thin layer and let them sit for a few weeks before using them as mulch around your other pine tree.

 

Argh! I didn’t see this update before I moved the pile however, I was mindful of the fact that they would soak up any rainfall to prevent it getting to the soil so watered the tree for 15 mins last night and the pile of needles and cones after they were moved for another 15 minutes today.

I’m always aware of tending to the other pine as it’s close to a mature horse chestnut and is intended (desired) to provide an evergreen cover above the fence line in due course. It’s grown about 3 feet in 4 years so there isn’t anything particularly wrong with it other than the knock on impact it causes to other plants in that area when it’s looking for water.

 

The majority have been there for several months if the number of times the gutters have had to be cleared out is any indication :-D

 

It's years, rather than weeks or months, for those to break down.

Trees of that type close to each other are quite common round here. There's a house I pass almost every day which has a pine, a horse chestnut and a maple in the front garden, all very close together - ie with touching canopies. We get adequate, regular rainfall, so it isn't a problem for those trees to thrive.
They're too close to give each one their 'fifteen minutes of fame' but they'll have been part of the existing woodland long before the houses were built, which is typical of this area.

 

The needles take so long to decompose because they have a waxy coating which tends to repel water and makes it hard for the bacteria to start degrading them. In this situation it means they won't absorb much rain, if any, but it's also why they don't make a great mulch compared to other things.

There is no reason not to use them but equally no major benefits either.

 

I was under the impression that pine trees are very drought resistant in most species.
They tend to grow naturally on fairly poor well drained soils.
I'm sure as with all things plant like there are a few exceptions.

I tend to think that as long as the soil underneath a mulch is damp it doesnt matter if the mulch is dry, it still stops evaporation.
Afterall, you could mulch it with old carpet, it has the same effect.

If the pine that is struggling is a similar size to the ones in the OP pictures I dont think a mulch will save it.

 

I agree with @Thevictorian in that the needles won't absorb moisture to any extent because of their nature.
Pine cones don't really break down much either, or certainly not quickly.
We also don't know the overall size of the other tree, and whether it was actively planted as opposed to one that's naturally occurred. I'm guessing it's the former though, because a naturally occurring plant of any kind will either establish well of it's own accord, or it won't thrive at all.
A well established pine will certainly manage drier conditions, and again - that's where one that arrives 'by itself' can thrive more readily.
Watering for fifteen mins really won't do much if it's very dry. A slow running hosepipe for about 30 mins to an hour, every few days, would be more useful. It'll get more moisture over autumn/winter once the h. chestnut becomes dormant, but it's the drier months that can make a difference to the establishment of any tree.
However, if you're still needing to water it after it's been in that length of time, it's possibly not the ideal choice for your site. They can take several years to start growing properly, but they aren't particularly speedy unless they have ideal conditions, and even then - they take many years to become sizeable.