How much CO2 might a healthy Douglas Fir ("Christmas") tree absorb during its lifetime?

I have donated 50 Douglas Fir trees (babies) as Christmas presents. They will be planted in a national park in a region native to their species, so they have a good chance of growing into adulthood, and are protected from deforestation.

Each tree comes with a (recycled) card that I am giving to my friends / family / colleagues. I would like to write a statistic in the card about how much CO2 their tree will likely absorb over its lifetime, but I haven’t been able to find this information. Can anyone help me?

Thank you!

(www.arborday.org/giveatree, in case you would like to check it out).