阅读下面这首诗，完成后面问题。
                                                                                                         春 日
                                                                                                （宋）吕祖谦 
                                                                            短短菰蒲①绿未齐，汀洲②水暖雁行低。 
                                                                            柳阴小艇无人管，自送流花下别溪。
【注释】①菰蒲：茭白，菖蒲。②汀洲：水中小洲。