Dwarf Mistletoe on pines

Arcto

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I've just relocated to central oregon, Collection in tow. I now live in an area of predominantly lodgepole pine forest with ponderosa pine as a minor component. All the lodgepole here are infected with dwarf mistletoe. A substantial amount of ponderosa also show infection although not as heavily. My research has found that while various mistletoes are species specific, there can be cross species infections. I've also have blue spruce with infections here. Interestingly, mugo pine and bristlecone pine show no infection.
Most written material recommends cutting off infected branches to stop spread. A crucial design branch or worse, a trunk infection kind of puts a damper on that method. One author recommended painting the mistletoe fruiting body with straight Roundup. I'm a little concerned about introducing a systemic herbicide to a host bonsai that way. Anyone else have to deal with this problem?
 

Bunjeh

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No. But I live about two hours north of you and you just scared the living sheeeeyat out me.
 

Adair M

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If the tree has mistletoe, the mistletoe will kill it. Eventually.

Why don't you do an experiment of painting roundup on a native infected tree's mistletoe and see what hs
 

Potawatomi13

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I had this once on collected Lodgepole. I had also heard the "it will kill the tree" comment. I think this is true only IF it isn't removed. IF it has not enlarged the branch at the infection to the point of unsightliness this might work. I tried cleaning it off till it didn't show. It started to grow back and I cleaned out an area deeper than the bark and it didn't grow back again. I didn't go much larger than the actual stem growth area. Like most trees the area will heal over eventually or can be used as shari. The idea of using Roundup might be worth a try but I'd try the other way first. Fear I do that it would go deeper into the trees blood stream.:eek:
 

Arcto

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Thanks for the input everyone! This is the first season here. So far, my collection is ok. When an infection comes, I'll try the bark cleaning method first. I talked to a local tree surgeon who told me that they climb and scrub branches on large ponderosas in Bend yearly at $600 a tree. People are willing to pay that to avoid losing old ponderosas on their property. I have some very large lodgepoles here that are heavily infected. However I noticed that they often die from lighting strikes or pine borer infestations before the mistletoe does them in. The irony is that there are some very nice yamadori ponderosa and lodgepoles in the area. But I won't collect any because of the risk of infection and re infection.
 

Arcto

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I have done an unscientific survey called "walking around my property" and checked all the existing conifers that have been here a while. I'm putting this out for people who live or relocate to a similar forest ecosystem, and those who introduce a infected lodgepole in or near an existing bonsai collection.
Lodgepole Pine: native dwarf mistletoe, rampant.
Ponderosa Pine: frequently infected.
Scotch Pine: frequently infected.
Mugo Pine: infrequently infected.
Bosnian Pine: infrequently infected.
Austrian Pine: no infection.
Western White Pine: no infection.
Bristlecone Pine: no infection.
Douglas Fir: no infection.
Norway Spruce: no infection.
Serbian Spruce: no infection.
Blue Spruce: no infection except a slightly smaller, broader, more blue unknown cultivar which has moderate infection.

Hope this is helpful. I may update this thread from time to time as my collection and landscape plantings have more time here.
 
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