Larix spp for landscaping

I grow trees in central Alberta, mostly for acreages. I have an opportunity to add L. occidentalis (western Larch) to my lineup. I already carry L. sibirica and L. laricina. (Tamarack) The seedlot I have was selected for 900-1600 meters in the Kootenai region.

In terms of landscape form and use, how would you say they differ?

Tamarack

• Native to my region (central Alberta)
• Tolerant of soggy acid soil. If sedges grow there, if moss is happy, you can grow tamarack.
• Relatively transparent crown.
• 60-80 feet
• Fall colour is BRIGHT yellow.

Siberian larch

• Non-native (but common shelterbelt tree.)
• Grows anywhere grass will grow.
• Drought tolerant.
• Somewhat salt tolerant
• Faster growth than tamarack
• Much bushier than tamarack (less transparent)
• Somewhat larger at maturity 80-100 feet.
• Fall colour often with an orange cast.

Western larch

• Closest native stand is in Kananaskis.
• May be borderline hardy in zone 3
• Faster growing than Siberian
• Soil preferences?
• Salt tolerance?
• Fastest growing of these larch.
• Mature height can approach 200 feet.

What have I missed? I'm not looking for features to tell them apart. I'm looking for features that would cause someone to choose one over the other for their acreage or woodlot.

 

Soil preference will be your problem for Western Larch - it is very fussy and doesn't like badly drained flat ground, only does well in well-drained mountain soils. It also isn't fast-growing; slower than Tamarack Larch when young, it will overtake that in the longer term, but I'd doubt it'd ever catch up with Siberian Larch away from its mountain homeland.

Have you tried European Larch? On good sites, it can be the fastest-growing larch of all (even outpacing Japanese Larch); it should be hardy in all but the coldest parts of Alberta. It too doesn't like boggy ground in the same way that Tamarack Larch does, but it is more tolerant of imperfectly drained soils than Western Larch.

 

Haven't found a canadian liner stock supplier for European Larch. Where possible I'm growing new trees that are candidates to replace forests as our climate warms. (We're facing 6-10 degrees by 2100) Trees that are native nearby get priority.

Good to know taht WL likes even drier conditions thatn SL. It would be a better candidate for southern Alberta, where sandy, fast draining soils are common.

Wet soils are uncommon here. In effect they are micro-zones, almost always associated with at least a run off channel, or other source of water.

 

That's not what I said! ;-) It actually needs moister soils; the difference is that mountain climates have much higher rainfall than adjacent lowlands, but the water they get is flowing water, highly aerated, and intermittent (draining quickly between rain spells), so less conducive to root disease fungi. What it can't tolerate is the stagnant, non-flowing water of moist lowland water-retentive soils, but not dry soil either – which makes it a very difficult species to grow successfully (given the locations most people want to grow their trees!).

 

I have had 2 batches now. Survival has been reasonable. The three year olds are now about 2 to 2.5 feet tall. In a few weeks we'll see how they handled our very cold February.