Thanks to everyone who replied to my request for recommendations. Apparently there are lots of us in Highland Park in need of arborist services because several people asked me to post the recommendations I received. Two arborists had multiple recommendations: - Brett Czarnecki at Treemasters: 412-450-8031 or *TreeMastersPghPA@gmail.com <TreeMastersPghPA@gmail.com> * - Stephen Miller with Bartlett Tree Experts: 724-863-8951 Several other arborists were also recommended: - Gary's Trees: 412-531-8733 - Keelan Brothers: 412-781-3415 - DC Culley Tree Service: 412-828-0811 - Sestilli nursery in Oakland - Davey Tree Expert Company - Lyle Blum Tree Service