Found this from a site

" Working wet soil will pack soil particles tightly, leaving less room for water and air to penetrate. Compacted soil also makes it more difficult for plant roots and gardening equipment to move through the soil. The compression forms tight clumps of soil that become hard as rocks upon drying and are difficult to break up. In addition to making it difficult for plants to grow, compacted soils also tend to drain more slowly, in turn delaying the ability to work the soil after the next rainfall.

Once compacted, it will take many years to rebuild a healthy soil structure, requiring annual applications of organic matter, such composted plant and animal wastes or perhaps growing a green manure crop, such as annual rye or winter wheat. "

Not sure how true this is though

Here is a link that might be useful: Resist the urge to work wet soil

The above post is very true I tilled my garden on the wet end last year when it finally dried up it was hard as a rock when it started raining the water just sat on top
it is pretty heavy clay here

Ahhh...This actually makes a lot of sense now. I was thinking in terms of chemical reactions, not physical changes in the actual structure.
Thank you all for the explanation. The scary thing is I was going to spray down the garden bed with water to make the tilling "easier" before I found out about this.

While soil does need to be moist to be workable, working wet soil, as has already been well described, is bad. A simple method to determine if your soil is "workable" is to take a handfull of that soil and squeeze it tightly and then poke that clump with your finger. If that clump then falls apart it is workable. If the clump stays together the soil is too wet. If that soil will not clump together it is too dry to work.

In a similar vein, you don't want to work bone dry soil either as you'll pulverize the peds which will reduce the void spaces in the soil volume.

Oops, just realized Kimmsr said something similar.

{{gwi:266126}} is not me but I've done something similar.

Lloyd

Hilarious! There's an old saying that goes like this...IT'S TOO WET TO PLOW.