Assuming the buds aren't dry and fall off when you touch then, excise one of the affected tips, cut the bud and the nearby tip in half lengthwise, and let us know what you see. Anything green? Any little tunnels? Etc.

The basic issue is that these dying buds are not getting enough water - something is jamming the xylem. Borers eat some of the xylem. fungi can clog it, roots can quit supplying enough water, etc.


If I am understanding correctly, this is also progressive - the problem is getting worse and spreading through the tree (as opposed to the affected tips are the same, just those are drying up day by day)?

• It seems unlikely your spray is causing the problem, unless you are spraying daily/weekly (if so, stop).
• This could indicate root problems. In my experience the roots are drowning. --> tip the pot so it stays inclined (15 to 30 degree slope, say); next time you water the tree, instead drench the roots with a solution of 2 tbls of (3%) hydrogen peroxide in a quart of water (kills phytophthora); keep it in full sun.

I assume you didn't repot recently (in which case, your tree doesn't have enough roots and you want to get it into some shade).

On the other hand, if the affected tips are on just one branch, I would consider removing that branch.
If it is just one of two or more tips of the same branch that are affected (i.e., the sibling tips are okay) I would consider removing just the affected tips (autopsy before tossy). More info ...

I've always repotted mugos in August, well after all new growth is hardened. Even at that, I lost one after doing some light root work and returning it to the same (relatively) shallow pot that it had been in for the previous three years. It suddenly started getting that lifeless grey overtone in the needles, not long after the repot. I lost another that I dug from the grow bed this past August. Otherwise, I've not been the least bit careful about the roots and the mugos have thrived (6 various cultivars of various sizes). The only thing that I can identify to have possibly been the cause is being potted deeply in relatively shallow pots.

My suggestion is that you keep the pot tilted15 to 30 degrees and return it to shade for a little while. Once buds stop withering, or it seems healthy despite the buds not moving, return it to full sun, but continue keeping it tilted. As long as the needles stay their normal bright green, it will be okay. Mugo needles last about 5 years and you can normally prune all the new shoot (just like JBP candle pruning) after it has hardened for 3-4 years in a row (it will back bud strongly). So, not to worry about the buds - worry more about the needle color. This may well not be what your tree is suffering from, but it will do no harm if I am wrong.

The catch-22 about root issues is that there is insufficient capacity to supply the foliage, so the foliage doesn't conduct as much photosynthesis, but this means lowered food/material and stimulus for root growth. So we must reduce the transpirational stress (shade and/or humidity tent) to get the foliage working, which then gets the roots growing, etc., etc.

Meanwhile, investigate the possibilities that pathogens involved further. Maybe someone else who has dealt with trouble similar to what your tree is experiencing will offer some insight into what is actually going on with your mugo.

Thanks Owen,

It's the only one I have and it was a well meant gift.  I'm trying to make the best of it.  At the very least, I'm learning some things.  My other pines are JBP and a few natives (loblolly, virginia).  Everything else is really healthy despite fighting off some needle cast on one last year.

-Chuck

  Sounds like it may be going zombie. Not alive yet not dead. It happens if you mess with mugo roots in the spring. I had one do it and Vance has seen it too. If it doesn't die outright this year there is hope it will grow next year.
  This is not me joking. Zombie mugos are real.

Here's a little update on this guy.

We had a very hot and very dry summer/fall in GA last year.  I think we were at drought conditions for part of the year.  I ended up moving this guy under some shade cloth and it seemed to do a little bit better.  All in all, I think I lost maybe 10% of the branch tips.

This year the plan is to just water and feed and not mess with it too much until I see noticeable vigor.  Then maybe I'll work some of the leggy branches back in and approach graft some buds closer in to the trunk.

Thanks for the interest,
Chuck

As to grafting I don't do grafting on Mugos and grow a lot them. 

Is that because they bud so readily you don't find it necessary, or because you've managed to work around it in your designs?