Recruiters for the apprenticeship programs of construction trade unions in northern Nevada walk a tightrope these days.They want to make sure that they're bringing on enough apprentices to meet the needs of today's construction market, no matter how slow it might appear, and they want to make sure that the construction trades could react to the arrival of big new jobs.They need to ensure, too, that the union construction trades continue to develop a cadre of skilled apprentices who will become the highly skilled journey-level workers for decades to come.But having felt the pain of the downturn like everyone else …