Montana Fruit Trees · Missoula, Montana

Rootstocks

Heads up: this isn't every rootstock out there. It's mainly the rootstocks our trees are grafted onto. A few of these we only graft a select few trees onto, but they're included all the same.

Every rootstock we graft on, lined up on one scale. The rootstock decides how big a tree gets, how soon it bears, whether it needs a stake, and how much cold its roots can take. Heights are typical mature heights for an unpruned tree. Vigor is how big the tree grows compared with the same variety on a seedling root.

24 rootstocks
4 fruit groups
Sizes checked against extension, trial and nursery sources · Sept 2026

Rootstock is everything below the graft union. It's what this page is about.
Bracket shows the published height range. Dashed means we estimated it from vigor because no direct height was published.
Stake means plan on staking or a trellis.
−40°F flag marks a Geneva or EMLA stock. Read the cold country note first.
Dashed canopy is Bud 118 in deeper, slightly more acidic soil. The solid tree is how it grows for us.
≈ marks an estimate. No direct figure was published, so it's worked out from vigor or from how we list it.

All four plates share one scale, with a 6 ft person on each for reference. Heights are to scale. Canopies are drawn a little narrower than life so the row fits.

Apple & crabappleMalus

9 rootstocks

Bud 118 carries about 90 of our apples and crabs. The seedling roots on the right, Dolgo and Siberian crab, are what we'd put in the coldest, most exposed spots.

Swipe sideways to see the whole row.

PearPyrus

5 rootstocks

The OHxF stocks stand up to fire blight and pear decline. Ussurian pear is the hardiest pear species there is. We also graft our quinces (Aromatnaya and Ravalli) onto OHxF 87, but there's no published size data for that pairing, so it isn't drawn here.

CherryPrunus avium, P. cerasus

4 rootstocks

The G in G12 stands for Gisela, bred in Giessen, Germany. It isn't a Geneva stock.

Plum, peach & apricotPrunus

6 rootstocks

Each tree is drawn for the fruit it mostly carries here: plums on the native stocks, peaches and nectarines on Lovell and Krymsk 86, apricots on Manchurian, almond on Siberian C. American plum is the most dwarfing root in this group, and it suckers a lot.

Field note · soil

Bud 118 runs smaller in Montana dirt

On paper, Bud 118 is a semi-standard, around 85–90% of a seedling tree. That isn't what we see. In our dry, calcareous Montana soils it acts more like a semi-dwarf.

Plant it in deeper, slightly more acidic ground and it can push closer to that semi-standard size, so space your trees for the soil you've actually got.

That kind of swing is normal. Kentucky Extension points out that the percent-of-standard figures are rough and vary a lot with soil type and region, and multi-state NC-140 trials found rootstock size rankings shifting from one site to the next.

Cold country

Where we wouldn't plant Geneva, EMLA or MM stocks

In our experience, the Geneva series (G.935 and G.890 on our list) and the EMLA and MM stocks (EMLA 26, EMLA 7, MM 111 and the rest) shouldn't go anywhere that can see −40°F. That goes double without consistent snow cover, and it's worst of all out in an open, unprotected field sitting low in its airshed, where frost settles.

Winters that can hit −40°F or colder
No consistent snow cover over the roots
An open field with no windbreak or shelter
Low in the airshed, where cold air pools

If your site can see −40°F, skip them. Every other box you check makes it worse. Bud 118, or a seedling root like Dolgo or Siberian crab, is what we'd plant there instead.

Roots are the weak link. They never get as hardy as the top of the tree. In freezing tests, EMLA 7 roots died at about 20°F and EMLA 26 roots at about 14°F. That's soil temperature, not air.
Snow is insulation. A good snowpack can hold the soil up to 20°F warmer than bare, exposed ground.
Cold air is heavy. On clear, still nights it runs downhill like water and pools in low ground, so a valley-bottom field can run a lot colder than a bench just above it.
Geneva stocks wake up early. Cornell's work shows G.935 and G.890 lose their cold hardiness early in spring, which is rough anywhere late cold snaps are normal.

The map: what grows on what

Every rootstock we use, what we graft onto it right now, and what the research says it'll do. Variety counts are from our catalog in September 2026.

Rootstock	What we graft on it	Size class	Vigor vs. seedling	Mature height	Field notes

Sources

Where sources disagreed, the ranges above cover the spread. Heights are for unpruned trees and will shift with your soil, water, pruning and the variety on top.