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When it comes to trees, branching out can be challenging

Fungus can kill while pine and insect can hamper its growth, notes outdoors columnist
20190511_Blister Rust_Valk Valley (6)
This is one of the many trees showing blister rot ... and causing our outdoors columnist some consternation this spring.

I pause and take a look at the daunting line of pine trees still ahead of me: "1,800 down and 400 to go."

The task at hand is the removal of the lower branches of these trees, rather like a bonsai project of gigantic proportion, however being done so not so much for manipulation of shape but rather for survival of the trees.

In the spring of 2009 we planted 10,300 trees of various species on our farm, a fabulous project funded by the province's 50 Million Trees Program. This massive project was created to assist landowners, particularly in southern Ontario, to reforest lands that were sitting idle.

The goals were multi, ranging from carbon sequestering by the trees, to oxygen production by the trees, to soil stabilization by the trees, to ensuring trees would be available for harvest in the future, to providing potential income to the landowners.

The initial cost to prepare the land, buy the seedlings and plant them with proper advice and supervision was split between the Province and the landowner. One heck of a great program.

The mix of new seedlings on our farm contained red oak, black walnut, black cherry, white pine and red pine.

Over the last 10 years we have devoted a pile of time and energy to ensure these trees grew at their best potentials. Over 1,000 were replaced when it became obvious that we had received a shipment of poorly handled red pine seedlings (the fragile roots had been crushed in shipping).

In the beginning, the former pasture was still producing tall grasses that threatened to smother the wee trees, so intensive mowing was required. Our efforts to ensure a quality stand of trees was noted by various woodlot organizations.

As part of the management plan for these trees there will be a series of thinning cuts done to allow the better trees to continue growing without as much competition from either side.

This is a standard forestry practice that has a good track record for producing high value logs. The catch is... it will be another 40 years at least before the pines are big enough to reap any financial reward, and double that time before the hardwoods are ready to sold as veneer logs.

Hopefully, my great-grandkids (as yet unborn and assumed to inherit the farm) will appreciate the upfront work done to ensure these tall and healthy trees.

But a few curves have been thrown at us, one being the arrival of a fungus that kills the white pine, and an insect that interferes with the proper growth of the white pine's branch development.

The fungus can be dealt with, to a degree, with great effort while the insect is unfettered to wreck havoc on the new growing shoots. Of all the trees planted, the 2,200 white pines are proving to be a challenge to ensure good growth.

The fungus is commonly called white pine blister rust, and is usually fatal to the tree if left unchecked. This fungus (called Cronartium ribicola) arrived in North America from China in 1900, and has spread very quickly from the west coast to the east coast thanks to the presence of two plant species: gooseberry and white pine.

Hard to say how it starts its life cycle, kind of like the question of which came first, the chicken or the egg?

There are five stages of spore development that occurs in its travel between the two plants. In the spring the already affected pine trees release bright yellow spores from infected fungal sites. the spores land on the new leaves of gooseberry and currant and undergo further growth; the fungus does not kill these host plants.

In the autumn the next generation of spores are released to the wind from the gooseberries to land on the needles of nearby white pines (fungus does not affect red pines).

The spores travel from the base of the needles into the stem and within a year manifest in a swelling that kills the outer branch. This swelling breaks open next spring and releases spores back to the nearby gooseberry shrubs.

The remaining fungus in the pine tree then travels to the main stem of the tree where it encircles the trunk and cuts off sap flow, thus killing the tree.

The pine trees most affected by blister rust are the young ones, those about ten years of age, as they have many tender branches available under the two metre height (the zone of spores floating in the wind).

If a person can find and cut off the infected branch before the fungus can travel to the trunk, the tree may be saved. And that is my quest at the moment, to remove all the branches below the two metre height.

It's a slow process, but then everything about tree production is a slow process. The second part of this notion of tree protection is the removal of any gooseberry shrubs within 900 feet of the pines.

And so it goes, loppers in hand, as I encircle each tree, inspecting every branch, clipping the diseased ones off, tallying the dead and dying, trying not to be discouraged at the discovery of yet another infected tree.

"1,900 trees pruned, 300 yet to go."

In case you noticed, yes this is the tree planting program just cut by our province's imbecile Premier and his cabinet of 'trained seals'. Disgusting and shameful to say the very least.