[Pil-pc-oceania] "Permaculture Plants" - Seedling Root Form Vs Commercial Rootstocks

[Graeme George - Earthcare Permaculture]

Laurence and others

I've also been pondering this question in relation to the rootstocks we 
use for our Hertitage Fruits Group grafting days and the performance of 
my own fruit trees.

Seedling rootstocks are widely used in the propagation of fruit trees. 
Most pears and nashis are grafted onto seedling/ Pyrus calleryana /D6. 
Granny Smith seedlings are widely used for full-sized apple trees, 
though HFG uses a range of dwarfing rootstocks to suit backyard growers. 
Peaches are mostly grown on seedlings of Elberta or Golden Queen (seeds 
from the canning industry). Persimmons are grafted onto seedlings of 
either American Persimmons or the Asian Kaki. White Sapote, Avocado and 
all citrus are also grown on seedling rootstock So we're talking mainly 
about apples on dwarfing rootstock, plums, cherries and apricots.

Deciduous fruits that require cross-pollination are notoriously variable 
when grown from seed and in the majority of cases the progeny are 
inferior to the parents. Nevertheless, I have two seedling apples and a 
plum that are among my most favoured and  productive trees, even though 
they don't have commercial potential. These are still growing where they 
came up and all they get is an occasional light pruning to tidy them up. 
I have the space here to allow such seedlings to demonstrate their 
potential before I decide whether to grub them out or not.

Some apples and many plums can be grown from cuttings, but grafting or 
budding onto a selected rootstock are the usual methods and a seedling 
rootstock can be quite satisfactory for this. Most peaches (and 
nectarines) are self-fertile, so their fruit comes fairly true to type 
and good results can be expected if these are grown from seed (poor 
performers can always be rogued out and replaced).

Use of seedlings as rootstock, per se, doesn't necessarily provide the 
best performance. Peaches are renowned as being shorter-lived than other 
fruits and in my experience they have a much higher water requirement in 
order to grow the vigorous new wood each season that bears the flowers 
for the next season (apples, pears, plums, apricots bear fruit on more 
permanent spurs). I understand that Marianna plum can be used for 
peaches, but this is a shallow rooted plum, that suits wet soils, and 
hence is not a good choice for really dry conditions. Most of my plum 
failures have been on Marianna rootstock and a row of these have been 
struggling this season with restricted watering - small fruit dropping 
prematurely, shoots and branches dying back, etc. I'm wondering how 
peaches might go on Myrobolan plum.

My established apples on Granny Smith seedlings and my pears and nashis 
on D6 do very well without any supplementary watering. The assumption is 
that they have their roots well down  and are accessing the water table. 
I give them regular deep watering during their first year to get them 
established and then restricted watering in subsequent years to 
encourage them to get their roots down deep.

The cherry plum Myrobolan H29C  is the favoured plum rootstock 
commercially in Victoria, though Marianna or peach seedlings are 
sometimes used. Myrobolan seems to perform better than Marianna in dry 
conditions. I also find that I have a better success rate with grafts on 
H29C than on Marianna. I have a few well-established plums that have 
cropped quite well this season with little irrigation. Last year some of 
these got badly sun-burnt in a dry spell, but this year, in even drier 
conditions, the trees have had good leaf cover and heavy crops with 
almost no sunburn. I assume that last season's stress has encouraged the 
roots to go deeper.

Now I haven't dug up any established trees to see what their roots are 
doing. Both Marianna and Myrobolan plum are grown from cuttings, with 
the roots growing as a circle of shoots from the calloused cambium layer 
at the base. Presumably Myrobolan does a better job than Marianna in 
converting some of these roots into substitute tap roots. Seedling 
cherry plums can be used as a rootstock if you have access to them and 
if you only want to do a few trees, but this is often discouraged as 
they tend to sucker a bit. Commercial plum rootstocks are supposedly 
selected for low suckering, but I still have to watch for suckers on 
some of mine, so using seedlings for small quantities is probably a good 
idea. Most apples are grown from either cuttings or suckers (stool 
bedding) and thus don't start off with a tap root either. I'm beginning 
to wonder whether it would be worth trying to grow some seedlings of the 
dwarfing apple rootstocks and see if they perform better than cuttings. 
One disadvantage might be a greater degree of variability in performance.

I question the Fukuoka method of no intervention and letting  fruit 
trees do their own thing, particularly if one has limited space. This 
may work satisfactorily if one has the luxury of acreage, good soils and 
a benign climate. It is no doubt a wise policy for trees that still 
retain most of their wild characteristics, eg nuts. However, most of our 
temperate deciduous fruit varieties are highly domesticated with complex 
genetics (centuries of cross-breeding and hybridisation) and have been 
selected for fruiting characteristics under conditions of cultivation, 
not their ability to survive as a wild tree. One only has to look at a 
self-sown apple tree growing by a roadside to see what a tangled mess 
they can get themselves into without human intervention. I liken this to 
the reliance domesticated animals have on their human keepers. In the 
poultry world one would contrast the Guinea Fowl, which is still pretty 
wild, with the Turkey, that relies on AI for breeding and the light 
breeds of chooks that don't hatch their own eggs any more.

Our choice of  growing trees from seed, cuttings or from suckers will 
depend therefore on the nature of the species/variety and the context in 
which we want to grow them. In Permaculture I believe we need to make a 
clear distinction between "Food Forests" which should be made up of 
those species and varieties that can be productive under low maintenance 
conditions and "Orchards" comprising those trees that require intensive 
management. We get back to terminology here, but Permaculture is about 
functional design and we need to be quite clear about function, needs 
and products when putting systems together. A pattern language that 
helps us to do this is sorely needed. A few fruit trees in a zone 1 
backyard can be intensively managed, so choice of rootstock may be less 
critical. Food Forests are by their nature a pattern for zone 2. In the 
light of this discussion it's worth considering whether use of seedlings 
rather than cutting-grown rootstocks in zone 2 and 3 orchard situations 
might be a way of reducing inputs and hence be more sustainable than 
modern orcharding's move towards intensive production on trellises using 
dwarfing rootstocks.

Thanks Laurence for bringing this up.

Cheers

Graeme

PS : I'm on silty sedimentary soils on the footslopes of the Great 
Dividing Range on the edge of the Yarra Valley near Healesville, Victoria.


David Arnold wrote:
> Laurence, Susan, and Joel,
>  
> I have the experience here of seedling peaches and nectarines [10 of] 
> performing way better than conventionally propagated grafted peach and 
> nectarine seedlings.
>  
> Both were transplanted, but the seedlings were transplanted after one 
> year of growth in the vegetable garden, while I think the commercial 
> grafted trees would have had one year of seedling growth, then 
> grafted, then another year of growth before sale as 2 year old trees.  
> The commercially propagated trees may have already been transplanted 
> at least once, maybe twice or more, within the nursery farm before 
> sale to me.
>  
> The seedling trees came from seed of excellent quality Bd fruit 
> [Adrian Martin at Ruffy] which germinated in compost in the vegetable 
> garden. 
>  
> So in terms of nutritional start and number of times transplanted the 
> seedlings were already way ahead before planting out on-site.
>  
> I have read that the nutrition available to a corn seedling in the 
> first few weeks of growth determines the ultimate number of kernels on 
> the cob.  Some similar factors may apply to fruit tree seedlings.
>  
> regards,
>  
> David
>  
> David Arnold
> Permaculture Designer
> 4446 Murchison Rd
> Violet Town VIC AUS 3669
> 03 5798 1679
> arnold.vt at gmail.com <mailto:arnold.vt at gmail.com>
>
>  
> On 25/01/07, *Laurence Gaffney* <lgaffney at bigpond.com 
> <mailto:lgaffney at bigpond.com>> wrote:
>
>     Hello Susan & Joel
>     I have wondered for some time whether or not the root form of
>     seedlings may (often/sometimes) be substantially different
>     (deep/er tap roots for instance) than to that of "cloned"
>     rootstocks.Their does not seem to be much information around on
>     this point. (hence there may not be a point)
>     The wild harvest referred to may be predominantly from non-grafted
>     seedling fruit ?
>     The Fukuokan Philosophy is that nature knows what it is doing. 
>     That is, nature usually grows trees from seed and that the Tree
>     "knows" what form it wants to be.
>     I am slowly coming to the belief that seedling fruit trees should
>     play a greater role in Permaculture Systems
>     than they appear to do currently. My own (very limited) experience
>     is that the seedling trees have less problems.There are many other
>     issues to consider I know (eg.size, palatability) , but general
>     hardiness and drought tolerance should be pretty high on our lists
>     I would think.
>      
>     Please comment folks
>      
>     Laurence Gaffney 
>      
>     Joel Meadows said:-
>     Dear Susan,
>     I often find that the quality of wild harvest is better, and
>     almost always more abundant (fruit per tree) than my managed,
>     prunned and netted (if I get to it before the possums do) trees.
>     It makes me think that Fukiama San (of the One Straw Revolution)
>     was right about not pruning trees and letting things go a bit wild
>     to get the best out of natural systems.
>     Susan Girard said:-
>     I for one harvest from fruit trees on council land, the plums this
>     year have been great and the apples are just coming into season.
>     Irritatingly they are often better than the fruit from my own trees.
>
>
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