How long can poplar wait

[brdmkr]

I have a friend that dropped off some poplar logs for me to saw.  I've never dealt with them before.  I told him that I was really busy and it would be some time before I could saw them.  Is the summer heat more (or less) of a problem for poplar in the log than say red oak?  It may be a month or 2 before I get them sawed.

[WDH]

I have had a lot of problems with poplar getting a black mildew coating and gray stain in the lumber on the green sawn lumber in the air drying stack in the heat of the summer. 

I suspect the logs will stain bad in this humid Georgia heat if left for several months.  I know that the lumber will readily stain in hot humid conditions in an air drying stack. 

[Ron Wenrich]

The logs stain in about a week or less after cutting when its hot.  You'll be able to smell the sour smell as the logs sit in the yard.  Once the stain is in the log, it always goes into the lumber.  It may look white when you saw it, but it'll probably stain.  The stain will only effect the sapwood.

WDH:  How's your air flow around the stack.  I graded some lumber that was allowed to air dry under a tree.  It was all black due to poor air flow and leaves dropping on the stack.  There were also piles of slabs and logs in the area that blocked flow. 

[WDH]

Ron, the air drying shed is open on three sides, so it generally gets pretty good airflow.  I have good results with walnut, oak, and cherry.  However, I have had problems with yellow poplar and soft maple.  I was using a stack 6 foot wide with 3/4" commercial stickers (broken ones procured from a big pine sawmill).  In the heat of summer here, I think that the 6 foot wide stack is too wide for poplar.  I reduced the width to 5 feet and that has helped a lot.  It can get 90% humidity and not a hint of wind or air movement in the dead of summer.  I think that my problem is a combination:  Poor air flow as you point out and a stack width that is too wide.

Soft maple is worse that poplar, but they are both very quick to stain if it gets super humid and hot.

[flip]

Had some end sealed pop. that we dropped and set outside the mill barn last summer and finally got around to cutting this last weekend.  The sap wood started turning a little gray but not soft or stained.  Got some nice 22" wide boards

[Ron Wenrich]

The gray is the stain.

Most mills in our area use a 42" stack.  Even the yards with predryers and kilns seem to keep everything at that size.  I'm sure its for ease of handling, but it may have something to do with drying in a stack.  I know our buyers want fresh cut and no spray on the white woods.  They put on sticks and have no problem.  So, stack width might play a bigger role.