Looks like eastern redcedar, Juniperus virginiana.

In 2010 I got seeds from several trees transplanted to a park in 1935 and they were not so tall like those in the pictures. My seedlings started to produce cones this year, but they are less than two feet tall. It seems they will take decades to reach their parent trees

well, just keep some of the sport on the host plant. It's not very serious to you yet but that's such a beautiful throw-off that it shouldn't be lost. I hate to repeat what you've said, but in all seriousness, it is serious to someone like me. I live and breathe conifer gardening and grow myself. Thanks for understanding. What you have there is like me finding a rose that's unlike any other and I just happen to work for Jackson and Perkins... Maybe you'd be willing to send me just a few cuttings next spring. That would be excellent. Thanks, Dax

2. Thuja occidentalis 'Ericoides' During many years we have been calling this "Chamaecyparis pisifera 'Squarrosa'". Later I found that in Garden centres across Europe it is called "Thuja occidentalis 'Ericoides'". I have found some nurseries to post pictures of this conifer under name "Chamaecyparis thyoides 'Ericoides'". Plant on the photo has been slightly trimmed. Please clarify if it is Thuja or Chamaecyparis. :-)