Random thoughs on Stratifying Chestnuts

[Telemark]

Even keeping my shop lights close to plants, I tend to get some lanky trees. I use safety flags from TSC as stakes. They are very thin and flex easily which young trees need. They keep them growing straight. After they are outside for a bit, they harden up and don't need the stakes.

I wonder if the lanky trees are due to lack of wind. Have you tried putting an oscillating fan on them for a half hour a day?

 

[IkemanTx]

Jack,

Thanks for the advice. I didn't want to add damp sphagnum too early in fear of radicals starting before I was ready to plant. I won't be back on the east coast until mid or possibly late April. The chestnuts are in my dads care and I don't want him to have to plant and care for 40+ chestnuts.

I'd like to plant (direct seed and tube) them with a good radical but isn't it possible for them to be too far along? If not, I'll have him add sphagnum in a few weeks. Could you define "hydrate" for me. They have had a damp paper towel in the bag for a few months to keep them from drying out but have not been soaked. Thanks!

Sure, by hydrate, I don't mean adding additional moisture to the bag like a damp paper towel or medium. When you get nuts, depending on how they were collected, stored, or shipped, they can lose moisture content inside the nut. If I don't collect the nuts myself fresh from the tree, I typically wash them off individually under running water. Mold can move from nut to nut quickly but not be visible yet. I try to wash off anything I can. I don't use bleach a bleach solution like some folks. I found that bleach reacts with the shell can actually make mold issues worse. Once year I had a mold issue and tried washing individual nuts in a 10% bleach solution. The reaction between the nut shell and the bleach burned the hair off my knuckles. I think bleach can compromise the shell making it easier for mold to penetrate the nut.

Back to hydration. So, after I wash the nuts (I don't bother if I pick the nuts from the tree myself and know they are fresh), I put them in a bowl and fill it with water. I let them sit in it over night. This gives the nuts a chance to fully hydrate. I then remove them from the water pad the excess water from the outside and put them in for cold stratification. The nuts are fully hydrated but have no added moisture at that point.

It is the added moisture from the damp sphagnum in the bag that they need for cold stratification. If you are trying to put them in suspended animation, I would fully hydrate them but not add any source of water inside the bag.

Thanks,

Jack

Yoder,

If I am looking at direct seeding into the ground no earlier than January 1st of next year (removal of cattle off the place). Would this “suspended animation” allow me to wait until then to get them in the ground? Could I suspend them, then plant in the ground Jan 1 and get the rest of the needed cold stratification in the ground? I am located in zone 7B, so our winters aren’t near as cold as they are in other places. Our last frost date (30% chance) is April 2nd for reference.

I would definitely have protection for the nut until tree tubes are on germinated seedlings... be it metal cans, pvc pipe, or gutter downspout cut to length. I also assume that will help with locating the seedlings in the field. Instead of prepping all of the ground cover at planting time, could I minimize the threat of wasted mulch and weed mat expenses by waiting until nuts show signs of germinating before installing ground cover?


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[yoderjac]

Yoder,

If I am looking at direct seeding into the ground no earlier than January 1st of next year (removal of cattle off the place). Would this “suspended animation” allow me to wait until then to get them in the ground? Could I suspend them, then plant in the ground Jan 1 and get the rest of the needed cold stratification in the ground? I am located in zone 7B, so our winters aren’t near as cold as they are in other places. Our last frost date (30% chance) is April 2nd for reference.

I would definitely have protection for the nut until tree tubes are on germinated seedlings... be it metal cans, pvc pipe, or gutter downspout cut to length. I also assume that will help with locating the seedlings in the field. Instead of prepping all of the ground cover at planting time, could I minimize the threat of wasted mulch and weed mat expenses by waiting until nuts show signs of germinating before installing ground cover?


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The suspended animation approach can work but it has risks. If the moisture content is too high you will get cold stratification and potentially mold. If the moisture content is too low you can kill the nut. I have tried the suspended animation approach to time my seedlings but it did not work out well for me. A guy who posted on the old QDMA site with the handle of IndianSam has put nuts into suspended animation for over a year and germinated them. Big8 who posts here from time to time, starts his nuts this way and then adds moisture to time them and it seems to work well for him.

As for you second question, Sure. You can direct seed them in the fall or winter with protection. They need 60 to 90 days of cold stratification. I'm in zone 7B in VA and direct seeding them in Jan provides plenty of time for cold stratification.

As for minimizing resource waste, as long as they are protected, you can wait until they show top growth. Chickenlittle favors direct seeding in his area and does a lot more of it than I do. I've done a little, but not much, and resource wasting is part of the reason. One reason I start them indoors under lights is because I can cull them. I start with many more nuts than I need. Some nuts won't germinate. Some will germinate but struggle. Some will grow OK, and some with really thrive. I cull each step along the way. My soils are heavy clay and not well drained. This is not ideal for chestnut but they will grow in my soils. By keeping them at home where they are growing in medium in a root pruning container system they grow much faster than in my soils without care (farm is an hour and a half away). If things go reasonably well I can get 6' trees in 1 growing season (http://www.habitat-talk.com/index.p...h-rootmakers-transfered-from-qdma-forum.5556/). Once trees are this large with the dense root system, they do much better in my soils. There is a high initial setup cost for my method, but when used with many trees over a number of years, the setup cost is amortized pretty fast. However, if you only plan to plant chestnuts for a year or two, direct seeding may be a better option. It may also be a better option in climates or soils that are more drought prone.

Chickenlittle can probably provide better hands-on advice for direct seeding than I can, but you are generally headed in the right direction.

Thanks,

Jack

 

[IkemanTx]

Excellent.
Your success in 7B gives me hope for direct seeding. I wasn’t looking forward to either the cost or work involved with propagating them myself. My work pulls me out of state 18-21 days a month, and I have found it nearly impossible to keep plants alive in the Texas heat not being there to baby them, and what plants I have managed to keep from getting scorched have averaged only 2-3’ of growth in a season. I feel like a direct seeded nut could probably match that amount of growth, especially with some supplemental fert and a little water in dry spells.


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[Benja]

Growing trees in smooth sided containers causes roots to circle or j-hook. While these trees can look fine when young, eventually the roots constrict themselves as the trees get old. You don't have this issue when you direct seed trees, just trees grown in containers.

Dr. Whitcomb did a lot of the early research on air pruning. In the old days they cut the bottoms out of milk cartons. Whitcomb has a bunch of technical papers available but here is a general summary:

When a tap root hits air, it desiccates and stops growing. This causes the tree to produce secondary roots called upstream branching. Most of this branching occurs in the last 4" of root prior to the pruning point. This natural desiccation of the root does not leave an open wound which can be an entry point for disease as manual pruning does. When these secondary roots hit air, the process repeats creating more upstream branching and tertiary roots and so on.

The efficiency of absorbing water and nutrition for growth is a function of the number of fine terminal root tips, not the length of the roots. In nature, trees grow long tap roots as insurance. This ensures they get access to water during a drought if the top foot or two of soils dry out. When trees get large enough this generally is not an issue in most places except perhaps arid regions but it can be life or death with younger trees. They trade maximizing growth for a lower risk of complete death.

Keep in mind that while a tree with many fine terminal root tips is more efficient, they can only extract water and nutrients from where they reach. That is why you need a series of containers to grow root pruned trees. You start with a small container called an 18. They are designed with an appropriate taper that redirects roots to the openings and are "hung" from some kind of rack so air flows below the container. If you planted directly from an 18 into the field, while the tree would have a great root system for its age, the root ball would only reach a few inches in each direction. Having the top few inches of soil dry out is common in most climates from time to time which will kill the tree. The second stage container should allow approximately 4" on all three sides of the root ball. It can be a bit more or less, this is not critical, but if you use too large of a container for your second stage you will get less root pruning since most of that upstream branching occurs in the last 4". There are several designs containers use for this second stage. I typically use 1 gal Rootbuilder II containers from Rootmaker for this but other guys have good success with other designs as well. Whitcomb designed the Rootmaker containers so they definitely conform to the principles of his research. The important thing is that the container design conforms to those principles, not the brand and as I say others use different brands with different degrees of success and failure. For the third stage I use 3 gal RB2s.

Hope this helps,

Jack

Jack, I'm curious to know what you think of the air pruning method used by Edible Acres in the latest video -

 

[yoderjac]

Looks to me like the method does a pretty poor job of root pruning. I'm just comparing the root development he shows to what I see with my rootmakers. Those roots are puny with very little branching and it sounds like it was a full season of growth. The root ball was much smaller than I get from 18s and that is before the season begins. At the end of a growing season, depending on the kind of tree, I've had 3 gal RB2s full of roots. They seem to miss the concept of a series of containers and the 4" rule.

Take a look at the pictures in this thread: http://www.habitat-talk.com/index.p...h-rootmakers-transfered-from-qdma-forum.5556/
It shows a single season development of some dunstan chestnuts. Granted, they do grow faster than the hazlenuts he shows in the video. I've planted trees directly from 18s and had very poor success rates. Keep in mind that I don't provide supplemental water for my trees in the field. I'm sure they would do OK if I did that. I'm not sure what his objectives are, but I would not recommend that method, at least for folks with objectives similar to mine.

Thanks,

Jack

 

[Benja]

Looks to me like the method does a pretty poor job of root pruning. I'm just comparing the root development he shows to what I see with my rootmakers. Those roots are puny with very little branching and it sounds like it was a full season of growth. The root ball was much smaller than I get from 18s and that is before the season begins. At the end of a growing season, depending on the kind of tree, I've had 3 gal RB2s full of roots. They seem to miss the concept of a series of containers and the 4" rule.

Take a look at the pictures in this thread: http://www.habitat-talk.com/index.p...h-rootmakers-transfered-from-qdma-forum.5556/
It shows a single season development of some dunstan chestnuts. Granted, they do grow faster than the hazlenuts he shows in the video. I've planted trees directly from 18s and had very poor success rates. Keep in mind that I don't provide supplemental water for my trees in the field. I'm sure they would do OK if I did that. I'm not sure what his objectives are, but I would not recommend that method, at least for folks with objectives similar to mine.

Thanks,

Jack

Thanks for the reply. I doubt his objectives are quite the same as yours. He demonstrates growing out hundreds of nuts for just a few dollars.

The growth you get is incredible. You demonstrate that by carefully caring for a hand selected group of seedlings, one can produce a mature (and possibly fruiting) tree in under four years.

 

[yoderjac]

Thanks for the reply. I doubt his objectives are quite the same as yours. He demonstrates growing out hundreds of nuts for just a few dollars.

The growth you get is incredible. You demonstrate that by carefully caring for a hand selected group of seedlings, one can produce a mature (and possibly fruiting) tree in under four years.

Yes, the objectives are different. I'm looking for a high (personal) volume of high quality trees for wildlife. I'm looking for them to provide significant deer food over the long haul as part of habitat improvement rather than a few trees for attraction. Because of the volume required, I need trees that are able to stand on their own with little maintenance in the field. Even with rootballs much larger than his coming from 18s, my trees would not survive. I also tried planting trees when they had filled a 1 gal RB2 which is a much larger root ball than an 18. They lived but few of them flourished. When I plant after a tree has filled a 3 gal RB2 which may take 1 season or two in my area depending on the kind of tree, they seem to thrive.

If you read the research, it is that successive transplant to larger and larger containers that really build the root system. I'm sure with sufficient after care his trees will grow. If you are interested in alternate methods for root development, look at a Missouri Gravel Bed.

Thanks,

Jack

 

[Benja]

My chestnuts are pushing radicles and I'm not ready! I suspect it's because I boiled them lightly. Have you ever seen this?

In past years I've had trouble with weevils hatching from my seed chestnuts. This year I experimented with ways to kill the eggs, but still retain viable seeds. Roasting them in the oven at low heat didn't work well for me, but dunking them in 160 degree water for 3 minutes worked well. I used a meat thermometer to spot check a few nuts and their internal temp was right at 125 degrees. In each experiment I dried the nuts out on a towel for 2 days then gathered them into a bucket for 2 weeks. Three increasingly-hot, oven-toasted batches sprouted the little grubs, but the boiled nuts didn't. So Great, we dumped all those nuts out for the wildlife and collected fresh nuts on 30.September. Out of 30# of chestnuts I kept 300 of the largest for eating and skimmed the very nicest 100 for seed. All 300 were boiled, then dried out for a week. Then the 100 seed nuts went into 4 separate bags and into the crisper around 8.October.

This week I checked on the them for the time. Over half of them had radicles. Many were three inches and dried out black, but others were shorter and still pale yellow. Two of the bags had significant white mold growth on the top and I threw out half of their seeds. Bottom line: I have fifty chestnuts in growing media two months before I expected.

Since I've collected chestnuts from the same trees for the past four years and have not had chestnuts sprout so early, I guess that boiling them sped up their sprouting. I'm curious to know, has anybody else had this experience?

 

[yoderjac]

No, I've always just bought my nuts from Chestnut Ridge of Pike County and I've never had a weevil problem with them. Someone did send me some chinese chestnuts that had weevils once and I just chucked the ones that had issues. I've never tried to boil mine so I don't know what effect that might have. Early sprouting has always been related to the amount of moisture in the medium during cold stratification. If your medium is more moist, that could contribute to earlier germination. I don't know anything about boiling.

Thanks,

Jack

 

[Benja]

No, I've always just bought my nuts from Chestnut Ridge of Pike County and I've never had a weevil problem with them. Someone did send me some chinese chestnuts that had weevils once and I just chucked the ones that had issues. I've never tried to boil mine so I don't know what effect that might have. Early sprouting has always been related to the amount of moisture in the medium during cold stratification. If your medium is more moist, that could contribute to earlier germination. I don't know anything about boiling.

Thanks,

Jack

That's a good point about moisture. I noticed a bit of water in the bottom of the bag so maybe I hadn't dried the nuts as much as I thought. They were being stored "dry", alone in a bag with no medium.

 

[yoderjac]

I wonder if boiling them softened the outer casing and water penetrated. I have no experience with boiling them. I'm just guessing as to a possible cause.

 

[Benja]

Thanks for your insights, Jack. It was a new experience for me, so I wanted to report it here.