Considerations for Temporary Tree Nursury Until Permaculture Land Planning Complete

We have 5 acres of flat and fairly wet (in points) old farmland here in Ohio.  We should have our earthship home fully completed this year (after 3 years of work...) and want to get 200-300 trees in the ground here this year.  The catch is, that because we've been focused on establishing shelter, we haven't fully planned out our land and want to ensure that we've thoughtfully prepared for our trees.  We plan on using swales to make the best use of the wet areas and have quite a bit of land sculpting to do as a result.  We will be ordering a large amount of our trees from our county's annual tree sale and had the idea that we could create a nursery for them right in front of our house so that we can get around to planting them when we've thought through all the possibilities.  The upside to this is that we'd be able to keep a close watch on them; keeping them mulched and watered appropriately and keeping deer fencing around them for protection.  The plan would be to get them in their final location a year from this upcoming spring.

Would the plastic tree guards be something that we should apply upon receiving and planting the trees in their temporary location or should we wait until they are in their permanent location to affix it?  We've not used them before but have heard that they speed up growth due to creating a warm, moist, micro-climate for the tree, however, I'm not sure how easy it would be to keep on when we transplant.  Any thoughts or considerations to creating this nursery would be much appreciated!

I would install the tree guards as you put them in the nursery bed.
In your case you can plant the baby trees very close together (I would leave about 1.5 feet clear between trunks), this will help them grow more upright with longer trunks which will be great for digging up for transplanting.
It is much easier to not harm the root ball if you have enough "handle" to maneuver the root ball once it is separated.

When I worked in nurseries we always kept the trees close together, in the case of trees that came to us in burlap covered root balls, we set them so the root balls were touching.
This creates a dense enough plant area that the trees have to grow mostly straight up to get sunlight, this gives you a very nicely shaped tree once planted in the permanent space of the buyer.
It also make it easy to keep weeds down so they don't compete with the trees, easier to cut the root ball free if it stays in place longer than anticipated too.

Redhawk

Redhawk, thank you so much for your insight!  I very much appreciate it  

depending on your location and automatic watering system is not that expensive and easy to set up. That means you can go away for some day without a problem.