Confusing Fertilizer

People are often mystified by plant food. There are three numbers on all fertilizers, like this 10-10-10. These numbers always stand for nitrogen, phosphorus, and potassium. These correlate to leaf growth, root growth and plant health.
If one is diligent with their plant, one can feed one's plant any plant food whatsoever.
However, if one is poor at plant care, even a perfect nutrient mix can weaken or kill a plant.
Fertilizers are made of salts, which dissolve in water. The plant is salty too, usually more so then the nutrient solution. When the salty water touches the salty plant, all the water involved (and the nutrients) go to the saltiest area.
When the plant is salty, then the plant absorbs the water and nutrients.
If one is over feeding one's plants, then there will be an accumulation of unabsorbed salts in the soil. One day this accumulation will result in the water/nutrient solution to be saltier then the plant. In this case the salty water inside the plant will be drawn outside the plant by the salty water/nutrient mix. When this sad thing happens, the plant will dehydrate, even though it is surrounded by water.

Nitrogen and Leaves

Nitrogen is the nutrient responsible for leaf growth. As such, some sadistic bonsai masters would restrict food from a plant during the spring growing season.

Taub's experiments were meant to determine the difference between low and high amounts of nitrogen feed in 19 species of grasses (1/10th strength and full strength of a complete nutrient product). It turned out there was a 34% increase in leaf mass; a 12% increase in the amount of leaves; but oddly, a 4% reduction in the size of those leaves.

I say feed, feed, feed.

Maples and Steer Manure

The manager of The Hillside Cannor Nurser told me that maples top dressed with steer manure are less likely to develop several maple blights. The most frequent maple blight averted is whatever causes twigs to blacken and die back.
I was thinking of screening some dried steer manure and replacing a portion of the bark in my soil mix with this. It may not be worth it, if I take proper care of my bonsai.
However, my garden stock could benefit from this - and it certainly wouldn't hurt them.

5 degrees or 15?

Some bonsai literature claims that tree roots don't grow when a tree is dormant. Trees go dormant when temperatures get below 15 degrees. Other bonsai literature claims tree roots grow until the temperature lowers to 5 degrees, and resumes at the same temperature in the spring.
Someone in the bonsai club suggested that it probably depends on the species. Therefore, this year I am keeping a list of which tree's roots are active at repotting time, and which are not.

On a related note, bonsai literature tends to assume that new root tips are sensitive to breakage, freezing, and chemical burn from fertilizers. But some other literature suggests that new roots, new root tips and roots in general are as hardy as they need to be. Hence cuttings, seedlings and newly repotted trees can all be fertilized normally.

Who Knows?