Frenz D A, Palmer M A, Hokanson J M, Scamehorn R T
Multidata, Inc., Minnetonka, MN 55305, USA.
Ann Allergy Asthma Immunol. 1995 Nov;75(5):417-22.
The most definitive reports concerning the seasonal characteristics of ragweed (Ambrosia spp) pollen dispersal in the United States date back 60 years to work conducted with gravity slide samples.
Volumetric pollen data from 23 sampling sites were used to study the ragweed pollen season.
The date of first and final pollen capture and the date with maximum airborne pollen concentration (the "peak date") were used to compare the pollen seasons at locations ranging from approximately 30 degrees N to 45 degrees N latitude.
Sixteen cities located north of 38 degrees N possessed similar peak dates (P = 1), generally achieving maximum airborne pollen concentration in late August or early September. Four cities located south of 38 degrees N experienced later peak dates, with the most southerly city reaching maximum pollen levels in mid-October. Three cities located in the Northwest did not recover ragweed pollen in air samples.
This study confirms earlier reports and suggests what time of year source avoidance is most critical for ragweed sensitive individuals in various locations.
关于美国豚草（Ambrosia spp）花粉传播季节特征的最权威报告可追溯到60年前，当时是通过重力载玻片样本进行研究的。
利用来自23个采样点的体积花粉数据研究豚草花粉季节。
首次和末次捕获花粉的日期以及空气中花粉浓度最高的日期（“峰值日期”）用于比较北纬约30度至45度地区的花粉季节。
北纬38度以北的16个城市峰值日期相似（P = 1），通常在8月下旬或9月初空气中花粉浓度达到最高。北纬38度以南的4个城市峰值日期较晚，最南端的城市在10月中旬达到最高花粉水平。位于西北部的3个城市在空气样本中未检测到豚草花粉。
本研究证实了早期报告，并表明一年中的什么时间避免接触花粉源对不同地区对豚草敏感的个体最为关键。
