Today I spent some time fertilizing 36 trees at the new Elba playground. The man at the nursery told me what to buy; a time release nursery fertilizer: 14,7,7. What he didn't tell me was that the price has almost doubled since the last time I bought it. A small bag is now $15! And I had to buy two to have enough for all the trees.
All my life I've know about the virtues of fertilizer. And all the different kinds, etc. When I was growing up we had organic fertilizer, not the synthetic kind that runs off the soil and poisons lakes and streams.

Daddy used cow manure, horse manure, chicken manure, rotten sawdust, to count a few. They used to make compost heaps, adding lime to layers to make the materials go through a heat. Now I go to the nursery or farm coop store and actually buy cow manure in a yellow bag. I was reluctant to do this a few years ago but found it is a great thing for roses.
Daddy used guano (nitrogen) to put into the soil when he planted peanuts. My job was to open up the big bags and take buckets of fertilizer to dump into the big "hopper" which was in front of the planter. Then when the corn was about knee high, we had to carry bags on our shoulder, hanging in front of us and filled with soda (ammonia sulfate) - tiny white pellets that made the corn grow. It's no wonder we didn't die from over exposure to all those chemicals since we handled them with our hands.
Daddy's vegetable garden thrived on the animal manure spread over the area and turned under with a plow or disk. When we first moved back to the farm, our neighbor gave us a load of chicken house fertilizer and it was fine until it rained and the sun came out and that was the worse odor I've ever smelled - hot ammonia scent filled the air. It finally went away. No more of that!
Jim put too much nitrogen on his pea patch one time and the vines grew like kudzu. I don't think he had many peas; all leaves. And then the Japanese beetles discovered them and had a good meal, eating the leaves and leaving the pea stalks sticking up into the air.