Reversions

[Steve Galehouse]

Many of the cultivated varieties of trees we use in landscape plantings bear little resemblance to their original species, and when reversions occur they are a surprise. Here is a photo of a "Dwarf Alberta" spruce(Picea glauca var. conica), which has reverted to its species of origin, white spruce(Picea glauca). Sort of like a toy poodle realizing that, deep down inside, it's really a grey wolf.

Steve

[Edward Frank]

Steve,

What is the difference between the cultivated variety and the original species? The genetic material must be there in the cultivar and be supressed somehow. I wonder what breaks the suppression? The same thing happens in other species also. We have hundreds of a varigated hosta lining our sidewalk and in patches around our long. Some plants sprouting from the same root mass will come up as a pure green variety instead of varigated. All of the offspring of the completely green plants will grow as green plants. The code for the varigation seems to be missing in these sprouts even if they originally were growing from the root mass of a varigated clump. I am not sure what is going on.

Ed Frank

[Steve Galehouse]

Ed-

I know most of the "dwarf" varieties of conifers are asexually propagated from "witches' brooms" that arise spontaneously on otherwise normal trees, so yes, the original genetic material is always present. Some sort of trauma must initiate the formation of the witches' brooms, but I don't know if it is fungal, bacterial, or insect/mite damage, or other.


Steve
Edward Frank said:

Steve,

What is the difference between the cultivated variety and the original species? The genetic material must be there in the cultivar and be supressed somehow. I wonder what breaks the suppression? The same thing happens in other species also. We have hundreds of a varigated hosta lining our sidewalk and in patches around our long. Some plants sprouting from the same root mass will come up as a pure green variety instead of varigated. All of the offspring of the completely green plants will grow as green plants. The code for the varigation seems to be missing in these sprouts even if they originally were growing from the root mass of a varigated clump. I am not sure what is going on.

Ed Frank

[Edward Frank]

Steve, I know the witches brooms in the limber pines at Craters of the Moon are a result of a fungal infection. I am not sure about others.

http://www.nativetreesociety.org/species/witchs_broom/witchs_broom.htm

[Boldylocks]

I love it! And what a beautiful photo too.. That tree has some beautiful pinecones coming out at the top too!


Boldy