Colonial Downs in Virginia opens Wednesday afternoon for its annual summer meet, a 33-day stand that will be dominated by turf racing and twilight post times.\r\nThis year&rsquo;s Colonial meet features several notable changes, including a shift in the racing schedule and seven fewer race days, as the track tries to reverse a significant decline in field size that impacted last year&rsquo;s 40-day meet. This year, instead of racing Saturday through Wednesday on a five-day per week schedule, Colonial will run four days a week, on Wednesdays, Thursdays, Saturdays, and Sundays, with post time at 5 p.m. on all days but Sunday, when first post will be 12:55 p.m.\r\nLast year, post time on Saturdays was 12:55 p.m., but Colonial officials said that they wanted to experiment with a twilight post time this year in order to allow patrons to avoid beach traffic and to offer live racing at a cooler time of the day.\r\nDespite last year&rsquo;s dip in field size, the opening-day card certainly is not suffering from a lack of entries. A total of 122 horses were entered for the nine-race card, which includes eight turf races. Seven of the turf races drew full fields of 14 horses.\r\nNow in its 15th year of operation, Colonial has historically been known for attracting full fields, in large part because of its expansive turf course and the track&rsquo;s practice of carding at least 80 percent of its races on the grass. But during last year&rsquo;s meet, field size dropped to 7.73 horses per race, down significantly from the 2009 figure of 8.89 horses per race.\r\nRacetracks across the country are struggling to fill races, in large part because of significant declines in the foal crop since 2006 and a glut of racing days. Accordingly, Colonial dropped one day of live racing per week from its schedule this year to limit racing opportunities.\r\nColonial&rsquo;s richest race, the $600,000 Virginia Derby, is scheduled for July 16, while the $500,000 Colonial Turf Cup is scheduled for June 18. The Turf Cup is now open to 3-year-olds and up, whereas last year the race was restricted to 3-year-olds. Because of the change in the race&rsquo;s conditions, the Turf Cup lost its Grade 2 status this year, but track officials are hoping to get the grade reinstated if the race succeeds in attracting high-quality fields.