Excel Formula: Create vertical list by returning column header of each non-blank cell in a horizontal range across multiple columns

[haruspication]

Starting in H2, I'm trying to find the correct excel array/formula that will scan the horizontal range $B2:$D2 and return the column header of each non-blank cell in the range in the order they appear, and then move down to $B3:$D3 and do the same, etc. (The dates listed in Column H would then correspond with the crops listed in Column G.)

I appreciate any help in the right direction.

[TABLE="class: grid, width: 600"]
<tbody>[TR]
[TD="align: center"][/TD]
[TD="align: center"]A[/TD]
[TD="align: center"]B[/TD]
[TD="align: center"]C[/TD]
[TD="align: center"]D[/TD]
[TD="align: center"]E[/TD]
[TD="align: center"]F[/TD]
[TD="align: center"]G[/TD]
[TD="align: center"]H[/TD]
[/TR]
[TR]
[TD]1[/TD]
[TD][/TD]
[TD]2-MAY[/TD]
[TD]9-MAY[/TD]
[TD]16-MAY[/TD]
[TD="align: center"]TOTAL
COUNT[/TD]
[TD][/TD]
[TD]CROP[/TD]
[TD="align: center"]PLANTING
DATES[/TD]
[/TR]
[TR]
[TD]2[/TD]
[TD]Crop1[/TD]
[TD]1[/TD]
[TD]1[/TD]
[TD][/TD]
[TD="align: center"]2[/TD]
[TD][/TD]
[TD]Crop1[/TD]
[TD]2-MAY[/TD]
[/TR]
[TR]
[TD]3[/TD]
[TD]Crop2[/TD]
[TD][/TD]
[TD]1[/TD]
[TD][/TD]
[TD="align: center"]1[/TD]
[TD][/TD]
[TD]Crop1[/TD]
[TD]9-MAY[/TD]
[/TR]
[TR]
[TD]4[/TD]
[TD]Crop3[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD="align: center"]0[/TD]
[TD][/TD]
[TD]Crop2[/TD]
[TD]9-MAY[/TD]
[/TR]
[TR]
[TD]5[/TD]
[TD]Crop4[/TD]
[TD][/TD]
[TD]1[/TD]
[TD]1[/TD]
[TD="align: center"]2[/TD]
[TD][/TD]
[TD]Crop4[/TD]
[TD]9-MAY[/TD]
[/TR]
[TR]
[TD]6[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD="align: center"][/TD]
[TD][/TD]
[TD]Crop4[/TD]
[TD]16-MAY[/TD]
[/TR]
[TR]
[TD]7[/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[TD="align: center"][/TD]
[TD][/TD]
[TD][/TD]
[TD][/TD]
[/TR]
</tbody>[/TABLE]


To see ARRAY formula in Column G, see: Skipping blank cells in list based on non-blank cell count in each row