If Rob Cohen knew that aid was on its way from Washington, circumstances would be different on his devastated pecan farms, which once spanned five counties and 1,400 acres. He and his brother would not have purchased an excavator and a bulldozer, expensive equipment they most likely will not need again to harvest pecans. Instead of laboring for six months on their own to clear away the thousands of trees knocked over by hurricane winds, they would have hired contractors to do it in three weeks.But with billions of dollars in relief for homes, farms and businesses stalled in Congress — and little movement over the past two weeks of spring recess — Mr. Cohen, 45, is instead three months behind in planting and wondering if help will ever arrive. Debris from Hurricane Michael — the remains of trees older than Mr. Cohen — still smoldered in his fields this past week as he burned away a generation of pecan groves felled by the storm this fall.