Is there anyway this code can be refactored? The only difference is the order by part.

Idealy I'd like to use a delegate/lamda expression so the code is reusable but I don't know how to conditionally add and remove the query operators OrderBy and OrderByDescending

var linq = new NorthwindDataContext();

        var query1 = linq.Customers
            .Where(c => c.ContactName.StartsWith("a"))
            .SelectMany(cus=>cus.Orders)
            .OrderBy(ord => ord.OrderDate)
            .Select(ord => ord.CustomerID);

        var query2 = linq.Customers
            .Where(c => c.ContactName.StartsWith("a"))
            .SelectMany(cus => cus.Orders)
            .OrderByDescending(ord => ord.OrderDate)
            .Select(ord => ord.CustomerID);