Juniperus/Cupressaceae Pollen

The study from which the following data was taken examined the timing and concentration of airborne pollen from 1987 to 1996 to determine the spring pollination periods of several types of pollen. The table shown here gives information regarding the concentration of Juniperus/Cupressaceae pollen in the air. Dates given are in days after January 1 and concentration is in pollen grains per cubic meter of air.

Year

Start Date

End Date

Season Length

Peak Conc.

Date of Peak

Season Total

1987

41

74

34

523

43

3335

1988

52

71

20

655

67

1708

1989

61

91

31

1057

71

2888

1990

38

81

44

1115

57

3607

1991

42

78

37

442

64

3533

1992

45

75

31

1156

51

3629

1993

39

100

62

1248

67

4823

1994

39

80

42

1311

62

4971

1995

50

77

28

1485

75

7316

1996

40

67

28

2027

53

6238

             

Mean

44 (2/13)

79 (3/20)

36

1102

61 (3/2)

4205

As can be seen in the table, Juniperus pollination began as early as February 7 (Day 38), and ended as late as April 10 (Day 100). However, the average season for airborne Juniperus pollen occurs between February 13 and March 20, and it is most abundant in the air around March 2.The following graph expresses the data in a manner that allows one to better visualize the conclusions drawn here.