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thecityman

Propagation biology

Ok, I'm gona ask you advanced people to dumb yourselves down just a little to help this newbie who is still trying to learn.... I've spent a lot of time watching you-tube videos (admittedly not the most dependable information source) on how to propagate a new tree from an old one using different methods. There are videos of people starting new trees from old ones of almost all types of fruit. They all talk about how much money one can save in doing this instead of buying a new tree, and most end with the person planting their new tree with roots into the ground. I think I can do this, but here is my question: WHAT ABOUT ROOT STOCK? What I mean is, I thought a big reason for buying a new tree at a nursery was so you could get a good quality fruit that was grafted onto a rootstock that is stronger/healthier/more suited to a given climate/size control, etc. WEll, if I just propagate a new tree by, lets say, air propagating it from a limb of one of my existing trees, it will not have good rootstock, right? Or at least it might not. ORRRR will the whole (new) tree be the rootstock of the old tree? I mean, is a propagated tree an identical copy of the old tree....meaning it will have the old tree's root system AND the old tree's top work/fruiting section? I doubt that....seems like it would just be the top/fruiting part of the old tree since that is what the cutting is grown off of, but if so, it seems like the roots you get would be a crap shoot. If the old tree's top could have produced a good root system, why would it have been grafted onto root stock in the first place. Last but not least, is propagating a new tree from an old one the biological equivalent of planting a seed from the old tree, something everyone says rarely works out. Are propagated trees equally unlikely to mature into high quality adult trees? Sorry this is so long, and I've tried to limit my dumb/elementary questions here since I know most of you are far more advanced and probably grow weary beginner level postings. But you've all been kind and helpful so far, and I hope you'll continue to put up with my occasional uninformed postings! Thanks.
Kevin

Comments (15)

  • Konrad___far_north
    10 years ago
    last modified: 9 years ago

    For the most part you're pretty well informed.

    Rootstock is chosen allot for your requirement, ...say, you want
    a tree which doesn't grow too tall, then look for a dwarfing rootstock,..tall tree, standard rootstock, some rootstock can handle drought or wet better, etc. etc..

    Allot of fruits, like apples, pears, plums, sweet cherries etc. don't grow well on their own root, ..not vigorous enough.
    A known fruit grafted to a known rootstock can give a known end result.

  • plumfan
    10 years ago
    last modified: 9 years ago

    How big of an apple tree are you trying to duplicate?

    City dwellers (with no deer) can easily mount apple to an M-27, M-9, P-22 and the like and arrive at a cute tree that would get decimated in a rural setting due to voracious deer!

    It really depends on your end goal.

  • tringblat
    10 years ago
    last modified: 9 years ago

    Your suspicions are really pretty good.

    Grafted trees have:
    - a rootstock which is grown for known traits including those for soil conditions, disease resistance and dwarfing.
    - the producing grafted portion which is a clone of the donor tree that provided the scion.

    This gives a known result as far as the fruit qualities as there are no differences in the genetics introduced via the flower, seed, pollen routine. If you think of it, a succession of trees grafted from one known tree is genetically a clone of one that was first written about before the printing press was invented. Not a twin, not a descendant, but a clone.

    You could graft a scion from one tree onto two different rootstocks and have a full sized tree (as big as the scion could/would) or a super-midget-micro dwarf.. different rootstocks but still genetically the same upper tree.

    Seeds are full blown gambling events with the full range of possibilities mathematically possible for the genes present. Chances of a reliable repetition of one tree's success, into the seeds of its fruit are, at best, miniscule.

    Genetically the grafted portion and the rootstock are not intertwined. If allowed to sprout shoots, a scion taken from the rootstock portion of a tree and rooted would have the qualities of the rootstock. A scion from above the graft would have only have genetic material from the upper grafted portion, not of the rootstock.

    That help any?? :)

  • thecityman, Zone 7a/6b near Nashville
    Original Author
    10 years ago
    last modified: 9 years ago

    As always, you have all been very helpful. Sounds like I was on the right track, but you all have certainly filled in a lot of the gray areas. Now that I have a better understanding of propagated trees vs. grafted vs seed grown, I can make better decisions. However, I'm still not too sure on when I can trust the root structure of a propagated scion vs when I would need to graft it to a more dependable rootstock. AS I said, I notice a lot of people create a viable scion with roots (via different ways, but lets say air propagation) and then cut the "new tree" away from the old one, then plant it in the ground and announce that they now have a new, free tree. But from what you all have just told me, what they really have is not a FULL copy (clone) of the old tree (assuming old tree was a typical nursery bought/grafted tree) but instead they have a full clone of the TOP (fruiting portion) of the old tree. I'm still not certain how I know whether a new tree created this way will have a good enough root structure to support itself, but from your answers I guess that depends on my needs. Plumfan, I'm actually more interested in creating some peach and cherry trees. If I could propogate new ones from my (or my neighbor's) existing trees, it could save me some money (not a big motivation since trees aren't THAT expensive) but also- I hope- help me to get "copies" of existing trees that I know produce well and are successful. IE...passing on good genes-EXACTLY. But since I can't know what root stock was under my "good" trees, I guess I can't really know if my new tree will really live up to the old one??? Oh well. Again, I appreciate everyone's help and patience. I really am learning here.
    Kevin

  • Konrad___far_north
    10 years ago
    last modified: 9 years ago

    Yes...you probably never know on what roots your [GOOD] trees are on but you could make your own rootstock from it by,...digging out some suckers or expose some of the roots by digging, they will shoot out new sprouts, replant the following year and graft on these with the top of the tree.

    When you mention about air propagation,.. i do layering, there are many way's doing it, you're doing this, first,..when you know before hand that root will form with ease, second, you'll know that this tree will perform good when growing on their own root, for instance, Evans Cherries are doing very well on their own root, very vigorous, can be used as rootstock for other cherries, ...but they're suckering!

  • thecityman, Zone 7a/6b near Nashville
    Original Author
    10 years ago
    last modified: 9 years ago

    Konrad_far_north- Thanks for the info. I am very likely using the wrong terminology when I say air layering. The propagation method I've seen most often, which seems to be the easiest (?) and which I'm most anxious to try is where you cut two rings around a limb on a tree about 3-5 inches apart, then a slit connects the two rings, then you pull the bark between the two rings off., so you are left with a 3-5 inch section of a small limb that has no bark. Then you wrap that area with sphagnum moss or peat moss or similar, wet it down, and cover it with saran wrap or tape or similar. You keep it moist and wait 1-2 months and, if all went well, roots develop inside the wet moss and you cut the roots and the rest of the branch away from the main tree. Then you either put it in a clear cup to monitor and continue root growth or you plant it in the ground right away. so what method is that? Layering, air propagation, or other? Sorry if my ignorance is showing....again! Anyway, the videos all end with people bragging that they have now created a brand new tree and no cost and which will produce as well as the tree it was taken from. My OP was questioning how they know it will produce as well as the original tree, since the original tree was (probably) made up of the top (which would be the same as the propagated tree) and some root stock, which would NOT be present on the new tree (right?). If the new tree will be so great without the original tree's root stock, why did they use rootstock on the original? I think most of the prio answers in this thread have addressed that, though, by saying basically that the new tree would be far more dependable than a seed from the original tree, but may NOT be the same or as good as the original tree with rootstock and top. By the way, what is the top part called on a grafted fruit tree? "Topstock"? I've never seen that word so I doubt it. Thanks all.

  • olpea
    10 years ago
    last modified: 9 years ago

    Kevin,

    Good questions. I wouldn't be overly concerned about rootstock. While rootstocks can convey characteristics like tree size reduction, increased precocity, cold tolerance, water tolerance, etc., unless you have a specific need, standard roots will do fine.

    Konrad offered some good information as usual, although I might question that poor vigor is a problem with fruit trees on their own roots.

    A big part of the reason nurseries suggest planting the graft union above the soil line on dwarf trees is so the scion portion doesn't root out and cause the tree to lose it's dwarfing characteristics.

    Here's a little background.

    Rootstocks dwarf by nature of some degree of incompatibility with the scion. This incompatibility disrupts the flow of carbohydrates and other nutrients producing a smaller sized tree. There is good research indicating the larger the portion of dwarf rootstock sticking up out of the ground, the greater the degree of incompatibility.

    Limiting the nutrient flow can cause positive things like increasing cold tolerance (i.e. forcing the tree into dormancy earlier) but many times it produces a more delicate tree requiring a higher level of management. Perhaps a biological analogy would be raising two children, one with optimum nutrition, the other on half rations. In most cases, the less fortunate child would be weaker, smaller, more prone to illness, and shorter lived.

    Sometimes the degree of incompatibility is too great, causing either long term graft failure or simply breakage at the graft union.

    Occasionally a rootstock will increase the flow of nutrients compared to a standard rootstock and produce a larger more vigorous tree. This happens only seldom. Generally it's the other way around.

    Naturally one might expect the fruit to be smaller on dwarf trees as well, but this is not the case. The reason being that most of the energy going into the fruit comes from the leaves, not the roots. In fact, the leaves export a significant amount of energy into the roots. That's why partially girdling a branch (i.e. choking it with a wire) will generally produce bigger fruit on that branch. The leaves use all their energy for the fruit with little or nothing to the root. This is also the reason some dwarf roots will produce marginally larger fruit. More leaf energy goes to the fruit and less to the roots.

    In times past, people were much less concerned about rootstock. Grafted apples were on seedling rootstock from Red Delicious apples. The primary reason Red Delicious seed was used was because Red Delicious was the most apple, and therefore the most common seed. Processing plants could collect large volumes of seed as they processed the apples The seed was inexpensive to purchase and trees performed fairly consistently on the rootstock.

    Same thing with peaches. Lovell rootstock was popularized because Lovell used to be a popular canning peach. Canners could sell the seed inexpensively. As far as I know, Lovell isn't canned today, but the seed hasn't lost popularity. Halford is still commercially canned today and is also a popular roostock.

    I grow my own peach roostock and haven't noticed any difference in performance from my own seedling rootstock and other more popular rootstocks like Halford, Lovell, etc.

    What you have described above is indeed called air layering. The reason most trees are not propagated by air layering is because it's much more economical to graft and success rates are generally higher.

    Lastly as an interesting aside, in rare cases the rootstock can convey it's own traits to the fruit. Tomatoes can be grafted onto poisonous nightshade plants (to which they are closely related). If grafted, the tomatoes will contain some of the poisonous alkaloids found in the rootstock.

  • thecityman, Zone 7a/6b near Nashville
    Original Author
    10 years ago
    last modified: 9 years ago

    Olpea- I always hope you will contribute to my threads because, as the example above demonstrates, you are not only knowledgeable but have a way of conveying that knowledge that makes it very understandable (ie the twins who are fed different diets). You also often spark new rabbit trails that I can't resist taking....like when you mentioned that grafting is more economical that air propagation. I am trying to not go off topic here, But why? I mean, as I understand it, to create a grafted tree I have to first create a rootstock (maybe by digging up a sprout or ?) Then you have to cut a scion and graft it to the root stock you had to create, Seems like it would be easier and cheaper to just remove a little bark, wrap it with some moss, wait till it makes roots, and plant it? So I would have thought grafting, which involves 2 trees and a good deal of time and effort, would be harder/more costly than getting a scion to root in place, then cutting it off and planting it?
    But back to the subject....I was fascinated to learn from your post that a dwarf is basically a way of interrupting and perhaps reducing the flow of nutrients in a tree. Very interesting. But before I even read that-and now even more- I already had the EXACT same question you said was fairly common....why don't dwarf trees make smaller fruit? Your answer to that may have been the best thing (of many) that I learned from your reply. If more leaf energy goes to the fruit on dwarf trees, then I get it. Of course, I'm now drawn (yet another rabbit trail you have sent me down) to your comments about putting a wire on a limb to choke it down so that less energy/nutrition is sent to the roots and more goes to the fruit, cause the fruit to be larger.....why don't people do this? I can imagine that if over done it could starve the roots and therefore the tree of required nutrition, but at least on a small level, it seems like it would be fun/interesting to create some supersized fruit? I want to try this on a small limb! :)
    Just a little more about your response, if I may. 1) How do you grow your own rootstock? By cutting sprouts or by planting seeds as you mentioned or how? 2) The general theme of your reply was that in many cases (I understand you were generalizing) root stock is not that critical and often a propagated tree's roots will be good enough to do the job. I'm going to take that to mean that I'll probably be ok if I propagate my own trees. Is using proven rootstock any more important to any particular fruits like peaches, plums, etc.
    BTW, it was neat reading that red delicious were common rootstock years ago because the apples were so popular and readily available at processing plants. I just recently read that many of the seeds used by John Chapman- "johnny appleseed"- came from cider mills- that he would go through their piles of cores and seed and pick out the seeds he would then use to plant on his journey. (sadly, though, they were apparently very low quality apples and/or sour apples. (I've been doing too much fruit tree reading!). Thanks again, Merry Christmas

  • drew51 SE MI Z5b/6a
    10 years ago
    last modified: 9 years ago

    With tomatoes grafting is because the rootstocks are resistant to early and late blight. and sometimes resistant to all three types of fusarium wilt. The main reason in tomatoes is disease resistance. So that isn't true with peaches?
    Some areas have such problems with wilt, the rootstocks are catching on with commercial growers.

  • Konrad___far_north
    10 years ago
    last modified: 9 years ago

    Thanks Olpea for your extensive explanation, you're right about, one shouldn't be overly concerned on rootstock,..that's definitely me on apples pears and plums.
    I've bought some apple trees on dwarf rootstock, ...after this first investment in fruit trees, I grown my own from seedlings, then grafted on these. After many years I found out that my trees are doing allot better then the dwarfing stock. Since I don't water, the dwarf, [shallow rooted] produces smaller apples. All seedling stock here don't grow into large trees, [harsh north], perhaps as large as southerners dwarfing stock, also, longevity is better on a seedling stock.

    I have grown some plums on their own roots but never ever they thrived, grafting to vigorous stock was allot better.

    The Evans sour cherry here does the best amongst all of the newer University of Saskatchewan pie cherries it seems. I'm now experimenting on grafting some to the more vigorous Evans and see, I'm pretty confident that some will improve in production.

  • thecityman, Zone 7a/6b near Nashville
    Original Author
    10 years ago
    last modified: 9 years ago

    Can I please slip in a quick, related question? All my trees are semi-dwarf but I just bought a new Honey crisp apple from Home Depot and the tag doesn't say dwarf, semidwarf, or standard. But it does say that the mature height is 14-30 ft tall, 15-25 ft wide. I assume that is a standard tree, do you think so? That's not my important question, it is: Assuming this tree is a standard tree, in the middle of all my other semi-dwarfs, is there any reason I can't keep at at approximately the same size as my semi dwarf trees? I understand that will probably require more frequent trimming/pruning, but with only one standard tree I'm ok with that...IF it will work? In terms of why I'd want to keep it at semi-dwarf size, partly just for appearance sake so my orchard will look fairly consistent. But also because all my trees are laid out and spaced for semi-dwarfs, so a standard tree at standard size would really crowd and shade its neighbor trees. Finally, I'd like to keep it small for the reasons people buy semi-dwarfs- ie ease of spraying, pruning, harvesting, etc from ground or step ladder. I'm sorry if this is off my original post, but it really is related since we are talking about root stock, etc. I'm asking if I can have a standard tree on standard root stock and still treat it like-and keep it at same size as- a semi dward. Other than more frequent trimming, would there be other advantages or disadvantages to this> thanks

  • olpea
    10 years ago
    last modified: 9 years ago

    Kevin,

    I'll try to answer some of your questions to the best of my knowledge.

    "grafting is more economical that air propagation. I am trying to not go off topic here, But why?"

    Picture commercial grafting for seedling rootstocks like peaches. The ground is prepared by machine. The seed is planted by machine. Seedlings emerge on their own. They can be spring budded the following year. Budding is extremely easy and fast. I've read an experienced crew of two can bud 1000 trees per day.

    Air layering is much more time consuming. Then once the shoot is separated from the tree, it requires much more attention than a rootstock already established in the ground and will not grow as vigorously (at least at first) as the grafted counterpart.

    Additionally air layering generally has a lower success rate, sometimes much lower. I've no doubt Konrad has good success w/ it, but he has an extremely green thumb. I've seen pictures of the precision in his grafts (i.e. perfect fit) and assume he takes the same attitude of craftsmanship in his air layering.

    T-budding is faster and more forgiving of relatively unskilled labor.

    "putting a wire on a limb to choke it down so that less energy/nutrition is sent to the roots and more goes to the fruit, cause the fruit to be larger.....why don't people do this?"

    Actually people do do it. There is a fairly well known peach breeder by the name of Paul Friday. I don't know if he still holds the world record for the largest peach, but he did at one time. It was done through girdling.

    On a commercial level, girdling is practiced on table grapes to make them larger.

    " How do you grow your own rootstock?"

    For peaches, the seeds sprout on their own from drops the previous summer. Generally I get more than enough seedlings for my purposes, but still plant more seeds. Seedlings are easier to manage in rows, vs randomly sprouting under trees.

    This summer I was a bit short of seedlings because my son couldn't seem to keep the glyphosate (i.e. herbicide) off them when spraying for weeds. I counted about 40 seedlings he killed.

    Apple seedlings are done the same way, except I dry the seed after I eat the apple and put them in a plastic bag which is kept in the fridge. In the spring I plant the seeds in a row.

    I plant peach seedlings right away from drops or cull fruit. I squish the fruit with my foot and gather the pits in a bucket. I use a hoe to make a furrow, spread the pits in the furrow and cover them with a little dirt using my foot.

    " Is using proven rootstock any more important to any particular fruits like peaches, plums, etc."

    As Drew alluded, for peaches it's important to use a proven rootstock for some areas. In some places, nematodes can devastate a peach grove. The rootstock Nemagard was developed for certain nematode resistance. Interestingly while Nemagard is resistant to some rootknot nematodes, it is highly susceptible to ring nematode, which is one of the main causes of peach tree short life (PTSL).

    PTSL can be a big problem in some areas. In those areas, the seedling rootstock called Guardian is recommended. Nematodes are more of a problem in very warm peach growing areas like FL, AL, GA. Nematodes also like very sandy soil. As I recall, you are dealing w/ clay and should have no worries with nematodes.

    You should be able to keep your apple tree a reasonable size by summer pruning. Pruning in the summer reduces some of the carbohydrate export from the leaves to the roots. I don't grow Honeycrisp, but my understanding is it's not a particularly vigorous variety anyway, so you shouldn't have any problem.

    This post was edited by olpea on Tue, Dec 24, 13 at 2:46

  • thecityman, Zone 7a/6b near Nashville
    Original Author
    10 years ago
    last modified: 9 years ago

    Olpea- That is one of the few responses that so full of useful information that I actually printed it out for future reference. As always, thank you so much for taking the time to be so thorough and informative. I'll resist the temptation to continue plying you for more information since you have been so helpful, but the moment I hit I'm going to go research what the heck "budding" or "spring budding" means in the context you used it (ie, it seems to refer to some kind of technique rather than the natural occurrence of buds developing on a tree each year.) Its always fun learning new things in this hobby! Thanks again.
    Kevin

  • Konrad___far_north
    10 years ago
    last modified: 9 years ago

    >>he takes the same attitude of craftsmanship in his air layering.Not really, most I do is layering or branch layering into the ground.

  • marknmt
    10 years ago
    last modified: 9 years ago

    Konrad is a skilled machinist (you can see some of his work on the metals forum) and considers anything done to less than a few 10 thousandths tolerance to be rough work.

    His grafts reflect his appreciation of a good fit.