Planted small group of mugo pines 10-12 (maybe 15) years ago. Did fine, but now they are starting to die. Old age?
These trees are expected to live up to 50 years, so I don't think it is old age that is killing them.
That looks like it is winter burn. Are all the trees browning in the same pattern? Has your area had harder than usual winters or has something around the trees changed that might change the flow of wind. This article will explain more:
https://www.gardeningknowhow.com/plant-problems/environmental/winter-burn-in-evergreens.htm
It may also be a fungus. If the trees are browning in different patterns from each other, haphazardly, this would be an indicator that the problem is fungal. If this the case, a fungicide should help clear it up.
Our Mugo Pine has white spots on it and is turning brown - are you familiar with this problem? It is about 45 years old.
This may be pine needle scale.
Here is a link with more information.
http://msue.anr.msu.edu/news/first_generation_pine_needle_scale_crawlers_should_be_hatching
https://www.gardeningknowhow.com/ornamental/trees/pine/mugo-pine-information.htm
I have white spots on my mugo pine. They are well established but are showing a decline with the white spots. How do I treat this and is it a major problem?
This is likely Pine Needle Scale.
Here is a link with more information.
http://msue.anr.msu.edu/news/first_generation_pine_needle_scale_crawlers_should_be_hatching
I planted 3 of the Mugo Pines in June on the east side of my house. They are sheltered but get lots of sun in the morning but are shaded in the afternoon. They have turned brown. In reviewing the internet for their care, they say they never need watering. I do water them in the summer but don't know if I am watering them enough or not. Please advise.
Either too much or too little water can cause browning in pines. There are also several pathogens that can cause this. The following article will help you:
https://www.gardeningknowhow.com/ornamental/trees/pine/pine-tree-browning.htm
dwarf mugo pine: Stems look white, which does not rub off. Also some browning of inter stems. Is this a fungus or disease or natural to the pine? Thank you.
Without an image, I believe you may have a Pine Scale infestation.
Here are some links with more information.
http://ento.psu.edu/extension/factsheets/pine-needle-scale
http://msue.anr.msu.edu/uploads/files/e2812.pdf
the mugo pine is out growing the space that it is in. we would like to reduce it size in width and height, is this possible to do without killing the pine. what is the best time to cut back on this plant.
This is a common complaint with Mugo Pine, they are sold as Dwarf varieties but can still grow or outgrow their space.
If you shorten the stems you will likely cut off the dormant buds and this will result in no new growth and the stem will die.
You can try to shorten the longest stems back to existing interior limbs that still have needles.
If you are successful in cutting the long stems back, next spring you can tip prune the shrub on each branch when once it's 1 inch long.
This will thicken the foliage. If the proposed cuts, will leave you with little foliage, you may want to dig it up and replace it.
https://www.gardeningknowhow.com/ornamental/trees/pine/mugo-pine-information.htm
I found many dead needles in the bottom of the topiary dwarf mugo pine when first grooming this summer. (I mean handfuls of these long needles!) I just planted it this year. Am I doing something wrong? The rest of the plant looks good and healthy right now.
These articles may help
https://www.gardeningknowhow.com/ornamental/trees/pine/pine-tree-browning.htm
https://www.gardeningknowhow.com/ornamental/trees/pine/diplodia-pine-tip-blight.htm