Answer: The Monrovia catalog description is currently incomplete for this cultivar and should be updated soon. So, in the meantime, here is a link to the Monrovia press release about this plant describing its smaller size as indicated in the article you read. You may need to cut and paste the complete url into your browser to make it work correctly.
I am not sure where you saw it described as larger, perhaps you were looking at the entry for Pinus nigra rather than Pinus nigra "Oregon Green". The species is certainly a much larger tree than this named cultivar which was selected in part due to its smaller size.
I hope this helps.
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