thisNZlife

6 REASONS TO PLANT OAKS ON YOUR BLOCK (& in your community)

Shade

Many oak species, especially when grown in the middle of a paddock, develop a huge spreading canopy that creates lots of shade.

On a hillside, it's often better to plant tightly spaced rows of oaks and/or prune to encourage a more upright form. This helps to prevent stock ‘camping' in one spot, which creates a build-up of manure that then washes into waterways during rain. The shadow of a tall, narrow tree moves more around the slope throughout the day and stock move with it.

Several species, called ‘live oaks,' are evergreen. One of the better known is the Holm oak (Q. ilex), and many Mexican species. Their small, leathery leaves stand up to wind better than their deciduous cousins.

Compost

“The best place to site a compost heap is under an oak tree.” I've spent a long time puzzling over this cryptic advice from John Jeavons, originator of the Grow Biointensive gardening method. I've come to think it's due in part to the shade offered, but also the amount of life in the soil where oak leaves have been left to slowly mulch down.

When I lived in town, I collected woolsacks of oak leaves from the nearby arboretum. The leaves were used as mulch in the orchard, added to compost heaps, and I made a specialist leaf mould compost to make potting mix.

Rachel’s tip: use thin layers of oak leaves in compost to prevent anaerobic matting.

Fungi

Oaks can be inoculated with truffles, a very hit-and-miss endeavour, or mushrooms that are more reliable.

Eric is determinedly experimenting with inoculating his young oaks with saffron milkcaps. That's partly because he likes eating them, but also because if inoculation is successful, the mycorrhizal associations will boost the growth of the trees.

Waste wood

Prunings and thinnings of oak trees are a famous substrate for growing mushrooms – nothing beats oak for growing shiitake mushrooms. The wood also makes good biochar and outstanding firewood if you can find no higher purpose for it.

Timber

It's worth planting oaks for their timber alone. It's famed for its beautiful grain, its strength, durability, and hardness. Oaks were a traditional tree of European coppice forests, providing a regular yield. The wood makes fantastic flooring timber (some American white oak is imported for this purpose) and building frames.

And as William Logan Bryant's book describes, without mighty ships built of oak, there would have been no English navy driving an era of exploration and colonisation. History would be very different.

Acorns for fodder

Oaks can produce multiple yields over different time frames. It can take from 5-20 years for a tree to produces acorns. The crop size varies year to year, with regular 'masting' (extremely heavy crops).

The size and sweetness of acorns varies between trees of the same species, even those planted in the same area. Acorns from the white oak group are sweeter, more palatable, and believed to be less likely to cause toxicity in stock.

Oaks NZ members report credible accounts of acorns proving toxic to cattle and sheep. The risk is highest to hungry sheep or cattle which suddenly gorge themselves when no other feed is available. While acorns can be an excellent supplement for stock, access to them needs careful management.

John and Liz Hancock run sheep and cattle on 65ha in drought-prone Martinborough. John says they lost sheep that gorged on Q. robur and Q. petraea acorns. They're now trialling cork (Q. suber) and Holm oaks (Q. ilex) specifically as an alternative feed at the end of dry summers.

“Stock must be introduced when there are very few acorns on the ground,” John warns. “But I've never lost one from eating acorns from the suber and ilex.

"And boy, do they go for them! Particularly clever sheep like Sussex, you put them in a paddock and they head straight for the trees. They will push each other out of the way to get them.”

However, the oaks aren't proving as valuable as the Hancocks hoped. Q. ilex doesn't produce acorns until long after the worst late-summer feed shortages are over. Q. suber has better timing but doesn't produce a decent crop of acorns every year.

There's no toxicity risk to deer. Oaks NZ member Gary Fleming feeds pruned branches and acorns to his deer, a common practice in the Himalayas.

“They love it,” he says. “They'll walk over chicory and clover to get to evergreen oaks.”

Acorns are scoffed by heritage pigs and sheep on Poaka Farm in Canterbury.

FEATURE

en-nz

2021-08-01T07:00:00.0000000Z

2021-08-01T07:00:00.0000000Z

https://thisnzlife.pressreader.com/article/281921661029573

NZ Lifestyle Magazine Group