The symptoms on these leaves suggests winter damage and normal decline of older leaves. There was a lot of winter damage reported this spring -- especially on broadleaf evergreens such as magnolias and hollies. Adrian Higgins of The Washington Post wrote an article about this recently:
"It was a rough winter for the Southern magnolia. But don’t give up on yours yet."
https://www.washingtonpost.com/lifestyle/home/it-was-a-rough-winter-for-the-southern-magnolia-but-do...     
Regarding flowering, does your tree get enough sunlight? If it is too shaded, that might be a reason for lack of flowering. Also, there is a good deal of variability among magnolia cultivars with regard to earliness and degree of flowering.

ckc

How do I protect my Magnolia in the winter?

Keep the magnolia well watered up until the ground freezes.  When watering, soak the soil several inches deep and then allow it dry between waterings.
 Avoid later summer fertilization as this stimulates late-season growth that does not have time to “harden off” properly and is more prone to winter injury.
If the magnolia is young and located in a windy area, you can use stakes and burlap about 18 inches from the plants to create a wind barrier. Do not drape the burlap over the shrubs. 
Here is our website on winter damage http://extension.umd.edu/hgic/winter-damage-trees-and-shrubs

mh

Thank you for your help!

You are welcome.

mh