Only severely stressed eastern white pine trees are susceptible to pine wilt, as this disease typically affects non-native pines such as Austrian pine (Pinus nigra) and Scotch pine (P. sylvestris).
My gut feeling is white pine decline due to environmental stressors and poor growing conditions (poorly drained, fine textured soils).
Please contact a certified arborist for an onsite inspection and assessment:
IL Arborist Assoc.: