Mark Shepard on plant disease

I'm in a similar zone probably a bit cooler than your Wisconsin Food forest here in North Central Michigan. I have had a problem in the past with peaches and have read information about replant disease. I now understand that there are some problems of planting PRUNUS varieties close to each other or where other PRUNUS varieties may have been planted and died in the past. You don't hear much about that in permaculture and also I have read that there are some companion plants that might be alleopathic in some way to PRUNUS variets, such as possibly strawberries, tomato and other nightshades, etc.

I have been planting a lot of fruit and nut trees over the years in a food forest setting, and I do have concerns in mixing varieties that might spread disease to other plants or be hosts to things that might damage other plants so this is of quite an interest to me and was wondering if you have any knowledge that you can share in this matter. I have 4 new peach, 2 new cherry and 25 new strawberry plants as well as an apple and 5 kiwi coming this spring and I really want to be careful not to put things in a position where they could be causing damage.

I have had problems with peaches that have died out when planted within 20 feet of other peaches (dwarfs) and when I tried to replant all but one died. I am moving the new peaches and cherries to areas where none have been planted in the past but then was also wondering about the same problem with other types of trees, heard it could also be possible with pears and apples. Thanks.

Cool observation. It makes sense that if an area could not support a species due to nutrients lvl, dry/wet, fungi/pest. That planting the same thing in or near the post will have the same result, unless some corrective measures where done assuming the right thing was corrected. Normally dwarf/bush type plants are weaker than the semi/regular cultivar, so the observation makes alot of sense.

Should we plant named cultivars expecting 10% to die in 3yrs and another 20% culled by us due to preferences. Is this unacceptable.

What if we plant from seed. What is the expected germination rate 50%, how much should we kill due to oversowing/space 25% and how much due to poor fit for site(soil/water/pest) 10% how about due to taste/look perference another 10%.


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Hi Brenda...
Yes... disease is an issue... In polycultures there are a lot of unknown factors going on and some are helping reduce disease incedence...
Long-term there are two things that we should once again turn to nature for the answers...

One is succession... the Prunus genus is a mid-succession plant. It gives way to shade tolerants and in the case of MI would give way to the northern hardwoods... Sugar maple, beech, yellow birch, eastern hemlock... Somehow you've got to change the conditions so that the prunus diseases are not an issue...

The biggest thing that we need to do is breed new varieties... Using Luther Burbank style mass-selection (read about it in Restoration Agriculture: http://www.forestag.com/book.html )

Buying the same old susceptible cultivars just ain't gonna cut it... Stop trying to keep things alive that want to die and stop fighting against the things that want to live... Plant a zillion seedlings and let the losers die. The only ones that can survive on your site will have some sort of resistance trick...

SO... I would address the issue either by going past the prunus phase of succession or start a massive seedling breeding program... HEre's a great way to get a seedling nursery started in a small space... http://littlehouseontheurbanprairie.wordpress.com/2010/11/06/chestnuts-and-hazels-for-the-future/

Mark Shepard wrote:Hi Brenda...
Plant a zillion seedlings and let the losers die. The only ones that can survive on your site will have some sort of resistance trick...

SO... I would address the issue either by going past the prunus phase of succession or start a massive seedling breeding program...

Yesss! Well Mark, you've convinced me to buy your book.

I've frequently been known to rant to my friends about the need to get away from just trying to engineer a better plant and accept the fact that if we would just keep planting massive amounts of the natural seeds nature will provide the solutions we need in way we can never imagine. Like you said, so what if a whole lot die, the ones that make it show they've got what it takes and their seeds have an increased chance of carrying that resistance trick.

Can't find a plant that fits the niche you want? Find the one that comes closest and grow a lot of it in conditions that gradually get closer to what you need with each successive generation, consistently 'culling the herd' by using seeds from only the most vigorous plants of each generation to start the next - not really different from how we deal with our livestock. Of course it all sounds easy, but when many plants takes multiple generations to even mature it's going to take even more generations of dedication and work to see a lot of the fruits of the initial labor.

If they are using the same root stock. Then its almost a given that they are going to have the exact same problems and the prunus family uses only 3 or so different root stock.

thanks Mark. I looked up your Little house on the urban prairie link on chestnuts and hazelnuts....both of which I already have growing on the property...I even got my first harvest off of 6 of my hazelnuts last fall, was so pleased.

as far as the prunus varieties..I have cherries, plums, peaches, apricots growing now on the property that are doing fine, the problem was one area where I had planted some and they had died and I tried to replant in the same area..therefor am moving to a new area with the plants that are coming this spring.

I have 3 peach trees growing fine in other areas now, 7 plums, several varieities of cherries including sweet, sour, ornamental and bush, 2 apricots and there are a lot of wild prunus varieties in the woods on the property..

I figured the one area where things were NOT succeeding were due to the transplant disease so I changed that area over to pear trees and they are doing OK there, one is suffering slightly but it might be for another reason..out of 10 pear trees one not thriving is not unusual.

Just wanted to know if you had any experience with or knowledge of the transplant disease and what species it affects..