I have a 100 year old monkey puzzle tree approximately 35ft- 40ft high. I am worried that it's branches are turning brown quite rapidly from the trunk out. The branch tips appear green with new growth and there are cones forming. Also of concern there is a lot of sap coming from the full length of the trunk. I was concerned a couple of years ago whilst clearing the ground under the canopy of brambles to plant a few blackcurrant bushes together with a strawberry bed and onions, when I noticed sap at the bottom of the trunk, investigation at the time suggested that this was normal. The ground under the tree now is again overgrown with brambles, thistle, bindweed, mares tail. About 6 years ago the plot next to it was dug out for foundations for a new building. The advice/instruction that was given (and strictly adhered to) was not to dig the ground under the, to not cut any root greater than 2 inches in diameter and to fence the area beneath the canopy. The concrete foundations were poured but the building has not been built. The area around the remains fenced off. Any advice or help with what may be able to be done to save the tree would be greatly appreciated. There is a TPO listed for the tree and it is recognised as a local landmark. I know there will be a lot of disappointed and upset people if it has to be removed. I am in north-west of England 20 miles from Scottish border.
Two things you will find unwelcome are immediately apparent in your pictures: 1. To be 100 years old at only 40 ft. tall it would have had to have averaged 4 in. per year, has clearly been growing a lot faster than that for some time now. So either it grew very slowly for a long time before starting the period of normal growth for the species or it is not 100 years old. 2. The browning and bleeding shows that it is on the way out. Perhaps due to hot and dry weather conditions. Otherwise the species has been having disease problems both in cultivation and in the wild. Araucaria araucana|monkey puzzle/RHS Gardening
It's on its way out, but it may have a good few years in it yet. Soil aeration & decompaction may well help improve it (soil compaction and poor drainage is a common cause of problems for the species) - it won't revive what's already brown, but may help stop further browning, and promote new growth at the top. Worth adding that even in the wild, they can live a long time with a minimal crown remaining at the top. So as long as the top is green and healthy, there's hope. File:Araucaria araucana - Parque Nacional ConguillĂo por lautaroj - 001.jpg - Wikimedia Commons File:Bosque primario 07.jpg - Wikimedia Commons
Phil West note the link to the RHS pages on honey fungus at the end of their profile of Araucaria araucana, I suggest looking at those if you haven't already and comparing what they describe with what you have going on.