How can I make this code run in parallel?

List<Crop> crops = new List<Crop>();
//Get up to 10 pages of data.
for (int i = 1; i < 10; i++)
{
    //i is basically used for paging.
    XDocument document = XDocument.Load(string.Format(url, i));

    crops.AddRange(from c in document.Descendants("CropType")
                   select new Crop
                   {
                       //The data here.
                   });
}