Lumber futures continue their wild ride, trading limit down after going limit up in the previous session. Futures fell the max $48 per 1,000 board feet, off 3.6% to $1,278.70.  But lumber prices are still up around 50% year to date and have tripled since the start of 2020.  Strong demand for U.S. homes in the midst of pandemic-related supply constraints have been the big factors in the surge in prices.  In addition, Canadian pine beetles are spreading across forests in Alberta.  But prices could be ...