When Does Wood Swell?

If we wire our trees, we might wonder this.

We notice that there are times of the year that wire bites in. And there are times that it doesn’t.

When should we be most alert? Here are a few pointers:

  • Every year, trees grow two annual rings.
  • If you were to cut a trunk, you’d see these two rings (the image below).
  • We tend to notice only the dark one, but there’s a light one too.
  • This lighter ring is put on in the spring and early summer. This wood tends to be less dense, and when exposed, rots faster.
  • The second ring is formed later in the year, in late summer and early fall. This is narrower and darker, as the tree isn’t growing as hard. This late season wood is denser and harder than the spring wood.
  • It’s best to look for tight wire in late spring and late summer.
  • If we skip one of these, then our wire can really get bitten in.
  • In the winter (in temperate climates) we can relax. No wood is growing. 

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  1. Ray Norris says:

    Great timing Michael, started last week removing wire thats biting.

  2. Colin Adams says:

    Thanks Michael. Would you say that there is sense in applying wire in the summer (except for the obvious issues with foliage, soft growth etc) so that a) the wire won’t cut in so much in the autumn as it would in spring/summer, and b) branches would set better when wired at the time that the harder wood is being laid down?

    • crataegus says:

      For deciduous trees summer is a great time to wire, much for this reason. But given that they’re easier to wire in the dormant season, that’s often the time chosen. Then, just being ever-ready to remove it in the late spring when wood builds. For conifers most wiring is done from mid-summer through late winter. When the plants are beginning to slow down.

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